Method is the mode or rule of accomplishing an end.
There are 2 methods of repertorisation.
#. Aggregation method
#. Elimination method

1. AGGREGATION METHOD / SCIENTIFIC METHOD.
In this all the analyzed symptoms are  written one after another and the indicated remedies are written against them depending on the process selected. The frequency of the appearance and the sum of marks scored by the medicines are calculated. This is the repertory value.
Advtg
No symptom however insignificant not neglected
Final outcome is the faithful reflection of the symptom expression in the drug pathogenesis.
Demerits
Laborious & time consuming
Both the prominently expressed symptom & vague symptoms are awarded the same status. 

2. ELIMINATION METHOD / ARTISTIC METHOD.
Dr. Margeret tyler introduced this method. In this method the symptoms are arranged in a hierarchy in accordance to the schools of philosophy of the selected repertory.
Eliminating symptoms are those symptoms which through of all the medicines that are not needed for the patient and bring only those medicines which are required for the patient.
The eliminating symptom is very important in the exercise of repertorisation because it dictate & determine the medicines that compete for the mantle of the similimum. It act as safe shortcut to the prescription in the hands of the experienced physician.
The elimination mode can be
#. Single step elimination
#. Cascading elimination

SINGLE STEP ELIMINATION
The elimination of the medicine is done only once, at the beginning of the exercise.
The most prominently characteristic symptom is selected as the eliminating symptom. The medicines indicated for this are noted down. For the next rubric / symptom ,only these medicines which are common to the eliminating symptom are considered.
Medicines outside the eliminating symptom _ whatever be its grade _ is not considered for repertorisation.

CASCADING ELIMINATION
In this method elimination is carried out thro' the whole  process
Each symptom became the eliminating symptom for the next symptom
Extreme caution & care should be taken in structuring the hierarchy of symptoms.
The symptoms have to be arranged in the descending order of importance.
The medicines in the first symptom / rubrics are noted down, for the second symptom only the medicines covers the first symptom are considered. On working out the third symptom only the medicines those are indicated against the second symptom are selected.
So first symptom is the eliminating to second symptom, second symptom is eliminating for third symptom and so on. Thus each symptom is the eliminating symptom for the next symptom. The repertory value of each medicines is worked out in exactly the same manner as in aggregation method.
ADVTG : Labor & time consumption greatly reduced
DIS ADVTG : If one is not thorough & effective while structuring the hierarchy of symptoms, he may fail.  

                                                                METHODS BY VARIOUS AUTHORS

1. KENTIAN METHOD
Useful in cases in which generals & particular symptoms stands out with  their modalities. This method of grouping from generals to particulars with important to mental generals is called Kantian method of repertorisation, which is the best and commonly used method.

2. HAHNEMANN & BOENNINGHAUSEN METHOD
When there is no mental symptoms but only particulars with associated concomitants / complete symptom. We can use TPB as our aid. This method is called Hahnemannian or Boenninghausen method.

3. WORKING ON PHYSICAL GENERALS
Cases with ill defined mental symptoms or concomitants ,but only physical generals. We may use any general repertory such as Kent, starts with physical generals ,next mental symptoms then particulars.

4. WORKING ON PECULIARITY
Cases having one or more peculiar symptoms with few generals & undefined symptoms, our aim is to find out the medicine which have that peculiar symptom and then proceed with vague or common symptoms. Any repertory which deal with the peculiarities can be used for this purposes.
This method of finding a medicine with the help of a peculiar symptom is called Keynote symptom method.

5. WORKING ON PATHOLOGICAL GENERALS.
When we come across patients with a few common symptoms or pathological symptoms only. The following details will help in the selection of medicines.
Patients personal history & family history
Temperament
Complexion, color & texture of skin
Particular organ or tissue affected
Location, character & physical aspects of lesion
Possible cause of illness.
When all the available symptoms are put together they may direct to the medicines.

6. WORKING ON TECHNICAL NOSOLOGY
Prescribing on   nosological diagnostic terms or lab investigations.
When nothing to prescribe upon and the patients presenting with diagnostic terms without any symptoms eg.aneurism,atheroma etc.we can use any of the clinical repertories such as Borger’s clinical repertory.
These would not help in the choice of medicine but will bring us close to a set of medicines.

TECRISATIONTECHNIQUS OF REPGGERTORISATION
Techniques Of Repertorisation

#. Thumb finger method / Book mark
#. Plain paper method
#. Repertory chart / Sheets
#. Cards
#. Computers  

THUMB FINGER / BOOK MARK TECHNIQUE
This method is meant for quick reference in a busy practice, for those who have more experience with the repertory.
Usably 2 or 3 characteristic symptoms are taken.
Book marks or thumb & fingers are placed at the pages where the selected rubrics are present. This rubrics are scanned visually, and the frequently occurring medicines which have higher grades are short listed for selecting the similimum.
Advtg
Useful when the symptoms are less in number
Useful when the rubrics indicate less number of medicines
No necessity of writing symptoms or medicines but only   mental work
Time taken is very less, useful for busy practitioners
Dis advtg
Visual errors can leads to failures
Little use when number of symptoms are more.   

PLAIN PAPER METHOD
The symptoms are written down on a plain paper, and the indicated remedies are written against them on the basis of the method and process selected. The similimimum is selected on the basis of repertory value.
This technique is very time consuming for the aggregation method, as each symptoms and its medicines have to be written down.
But  the elimination method can be conveniently and easily worked with the plain paper technique. The medicines are written one below the other and the grades are marked against them.
The first column of the grades represent the value of those medicines in the eliminating symptom. Subsequently the grades of the medicines of the other symptoms are marked. If a medicine found under the eliminating symptom is not indicated for any of the subsequent symptoms a zero mark is indicated at the symptom number against the medicine. This is for single step elimination.
For the cascading elimination as soon as the medicine hits a zero,it is disqualified from further repertorisation,thus eliminating it.

REPERTORY GRAPH TECHNIQUE
This is simple, more refined and scientific method. In this technique repertorisation is done on sheets when are skillfully and carefully devised to save the time and hard work and are specifically prepared for the repertory that is to be used.
The chart having number of rows and columns. Medicines are printed on the first column and the symptoms are written on first row. The marks scored by the medicines are represented in the blocks at the intersection of the symptoms and the medicines. The similimum is selected on the basis of repertory value.
This technique is useful for the aggregation method of repertorisation,because time consumption is very less.
It is unnecessary to use this technique for the elimination method for obvious reasons.
De merits
Medicines represented in the sheets are less in number
Only polychrests are predominantly represented.

CARD SYSTEM METHOD
  These are repertories which are in the form of prepared cards. Each card represent a symptom, cards are arranged together and the similimum is found out.
There is no need of writing down or book markings, only the cards are shuffled together. This system is outdated on the arrival of computers.

COMPUTERS
The utility of computers has extended to the various aspects of Homoeopathic treatment. The result of repertorisation can be instantly projected on the screen, with the rubrics repertoriesd,the medicines indicated and their value in each symptom, also display the repertory value of medicines repertorised.The result can also printed as a hard copy on the printer.
Advantages are limitless, the aggregation method can be conveniently used on the computer.
De merits
Doctor must have the necessary knowledge and aptitude to use the computer.

                                                      Dr.PATEL'S AUTO VISUAL REPERTORY SYSTEM
It is a mechanical device, practically no paper work is required. It is all automatic, marks are denoted by three different colors and visual throughout repertory work. You can even read your medicines which come automatically.
The auto visual repertory consists of 5505 auto strips and auto visual apparatus having 435 medicines on in numerical order from above downwards. Each medicines is provided with a code number. Each auto strip has a number on the top representing the rubric / symptom number in auto visual homoeopathic repertory.
Auto strip is grooved at several places, which represent the medicines, this grooves are in different colors or markings which indicate the gradation of drug in Kent's repertory.

REFERENCES
Patel.R.P : The art of case taking & repertorisation
Munir Ahmed : Introduction to repertorisation
Castro : Logic of repertories
Tiwari : Essentials of repertorisation
Dhawle : Princilpes & Practice of Homoeopathy.
Ritu : Study of repertory