There is a style of auditing for each class of auditor between Level 0 and 4. One style is taught on each level.

The main processes for each level are run according to the style taught. A fully trained auditor would of course use the appropriate style for each single action performed. Rehabs and some rudiments questions may be best done Guiding Style (taught on Level 2). But a new auditor has to start somewhere, and that is on Level 0 and Listen Style. By applying that, he will produce his Grade 0 releases and that is what Level 0 is all about. 
When fully trained he will still do the Grade 0 processes Listen Style.

Any auditing is done using the TRs. The TRs and the auditing comm cycle are the same in all subjective auditing.
 So what exactly do we mean by style, and how does that fit in with the TRs?

By style is meant method of performing actions. Style is how the auditor addresses his task.

The TRs are the same. The timing, the directness and the emphasis on certain TRs is what make up the differences among the styles.

Level Zero - listen Style
Level 0 is run Listen Style. Here the thing stressed is listening to the pc. The TR that comes closest to that is TR-0 Bullbait.

Since 'to listen' is part of the very definition of 'Auditor', this skill is part of any level and style. But in Listen Style it is the main thing. The auditor has to be able to listen - and not just confronting and ignoring. The length of time the auditor can sit and listen without tension or strain is a factor.

What the pc does is not a factor in judging the auditor's performance. But it is a well known fact that pc's will open up and talk to an auditor that really shows interest and listens.

To be a good listener has been part of confession and psycho-therapy since the beginning of time. In psycho-analysis the analyst usually does a number of unforgivable violations of this basic skill. He will evaluate, invalidate and 'put the itsa-line in' on the pc, meaning he will tell the pc what his problem is, etc.

So being able to listen, without invalidating, evaluating or interrupting is what you are taught here. It shouldn't be made more complicated than that.

Listen Style isn't the same as 'Itsa'. You could say it is an invitation to the pc to Itsa. But technically 'Itsa' is the action of the pc saying "It is a..." In other words, that is a pc action. So the auditor only uses a simple question, attention and interest to get the pc talking. To get the pc to itsa is beyond the scope of Listen Style.

Level One - Repetitive Style
Repetitive Style auditing uses TR-0 to 4 with nothing else added. It has also been called 'Rote Style' or 'Muzzled Style' (a muzzle being a leather device you put over a dog's muzzle, so he can't bite or eat).

It is a formal style where you cut away anything added to the TRs. Auditors would too often add comments, Q and A, start excursions or discussions, all which would mess up auditing badly. By teaching the student this formal approach and 'put a muzzle on him', he would only state the auditing command and acknowledge.

Repetitive processes are done this way. It is TR-0 to TR-4 only and nothing added.

It has been known for a long time, that pc's that didn't make gains and progress with partly trained auditors, who were permitted to 'two way comm' would immediately benefit when the auditor was 'muzzled' and only allowed to use formal TR-0 to TR-4. When the pc would originate it was handled exactly per TR-4.

On repetitive processes the auditor simply has to state the command or question, acknowledge the pc's answer and handle any originations by understanding and acknowledging what the pc said.

Repetitive Processing consists of clean, crisp, repetitive commands given and answered often. The pace is faster and there is more control than in Listen Style. There is no room for the pc wandering around.

A pc being audited on repetitive processes is being instructed in what the auditor does and how. He will even be trying a few 'Do birds fly?' (TR-3) to get the idea. Then he will know what to expect and what is expected from him. It is the number of auditing commands given and answered in any auditing period that adds up to case gains.

It may be a bit of a chock to go from total permissive Listen Style to totally controlled and crisp Repetitive Style. There is certainly enough difference for any student and pc to tell the difference.

There are many repetitive processes on the Grades 0-4.
There is a special TR for Repetitive Style, called Mutter TR. It is listed under CT-1.

Level Two - Guiding Style
Guiding Style consists of two parts: 1) two way communication and 2) Formal auditing. When done this way we have Guiding Style auditing.

The first step (2 way comm) is to guide the pc into some subject that has to be handled or finding out from the pc what exactly needs to be addressed and handled. When that has been established it is handled with formal repetitive commands.

For the student to be able to do this well, he must first master Listen Style and Formal Style.

The first thing to know about Guiding Style is to let the pc talk and itsa without interruptions. But you also elegantly have to get him steered onto the right subject where the auditor gets the job done with repetitive commands.

The auditor, to be able to do Guiding Style properly, has to be able to observe the pc - in other words, occupy the viewpoint of an auditor.

In Guiding Style the auditor first finds out what to handle - then he goes ahead and handles it.

In this style the auditor to a greater degree than on the previous styles, audits the pc in front of him.

In this type of auditing the auditor should audit for Tone Arm Action. That is how he finds what to run and determines if he found the right thing. He looks for large reads and Blowdowns on the two way comm step and when he finds it, he should be able to get good TA by running a repetitive process on this area. At this level the auditor can expect to handle a great deal of chronic out rudiments, PTP's, Overts and ARC breaks in life.

To be able to do that, the auditor has to have a pc 'Willing to talk to the auditor about his difficulties'. That takes an auditor that can ask the right questions, not repetitive questions, but guide the pc into talking about his difficulties, that need to be handled.

Expert TR-4 handling is the real difference from Level 1. The auditor has to make sure, he really understands what the pc means before he gives the acknowledgement. He guides the pc into specific areas and listens carefully to what he has to say.

Formal Overts and Withholds auditing, as much of Grade 2, can be done with Formal Style as taught on level One. But Guiding Style is used on confessional type auditing, where the pc is guided into divulge what is the real Overt on a subject.

Half acknowledgment (TR- 21/2) is also part of Guiding Style and used to keep the pc talking on a subject with a feeling he is being heard. A big or multiple acknowledgment is also taught here to 'shut up' a pc that is going off the subject.

Guiding Secondary Style differs from normal Guiding Style. It's done by (1) steering the pc with two way comm to reveal something or find out something, not immediately obvious. (2) What is revealed or uncovered is then handled by Itsa. So it is Steer plus Itsa. You guide the guy into talking about something and get a Tone Arm Blowdown and then you make him talk about it. You get the Tone Arm action out of it, and then while he's talking about it he mentions several new things that give Tone Arm action so you note those things down and you come back afterwards and talk about those things. That is the complete drill. The style is used in different actions, such as "Way to Happiness" Auditing (Ethics Integrity RD) and Confessional Auditing. In Confessional Auditing you may have to dig around to find the real Overt. Then you use your Withhold system questions to get the pc to itsa what was found.

Level Three - Abbreviated Style
In Abbreviated Style all extras are taken out.
On Level One the auditor would always use "I'll repeat the auditing command" before he does so. In Abbreviated Style the auditor omits this when it isn't necessary and simply goes ahead and repeats it when needed - say, if the pc has forgotten the command. So Abbreviated Style is not pure rote, but rather a sensible use of 'Repeat' statements, etc. Repetitive commands are still used.

Two-way communication are also used on Level 3.

Prep-checking and auditing by lists are taught at Level 3. On a Listing and Nulling process, a list question can give half a dozen answers in quick succession. The auditor would half ack the pc and simply let him go ahead.

The auditor is supposed to be able to observe the pc and see when he is done with answering the question. He can also see when the pc isn't done by his expression (like a puzzled look) and will make sure to get all of the answer.

The auditor has to be capable of checking a question on the Meter and if it is clean, simply go on down the list. If any kind of protest or puzzlement the auditor should be able to pick it up and handle.

It is crisp and direct auditing, like getting to the charged point of a list quickly and smoothly. Often when auditing by prepared lists the pc will be sitting in some By-passed Charge and you want to find it quickly and correctly without attracting any attention to the auditor or the session form.

Level Four - Direct Style
By Direct we mean straight, concentrated, intense and applied in a direct manner. We don't mean to direct in the sense of guiding.

We put the pc's attention on the Bank and anything the auditor does is calculated to accomplish that directness by the shortest way. If we have the pc doing itsa on a command and really doing well, we would simply let him keep going and just give him enough commands to keep it going.

It can look real easy, but it takes an auditor that is on the ball. It is laser beam style. The auditor gets the pc started and may not have anything to do for a while, except make sure the pc is on the right track. If not, the auditor steps in quickly and gets the pc going in the right direction again quickly and smoothly.

If the pc is in an ARC break you don't want him to do a lot of talking (you don't audit over an ARC break). You may simply ask the pc to be quiet, while you do the Assessment and find the By-passed Charge.

The auditor's ability to control such a situation and keep the pc quiet without upsetting him, requires good direct auditing.

It is not feasible here to make a complete list of what processes are audited by which style. The above styles should be used as a reference. The right place to sort out what style to use is in drilling of the processes. Keep these styles in mind in drilling and you can easily figure out which style to  apply.