For the precise and rational selection of required rubrics a thorough familiarity with the construction of repertory and philosophical background is very essential.

We may adopt any of the following methods...
#. Direct selection #. Rubric search
#. Interpretation #. Synonyms
#. Cross references #. Synthesis of the rubrics

1.DIRECT SELECTION
In this method we can directly search to the required rubric, because it is available in the required form.
Eg. Complaints of nursing children
Generalities . Nursing children
Precaceous puberty
Genit. Female,menses before the proper age

2. RUBRIC SEARCH
In this method the rubric may present in the direct form, but it is not as easily available as in the direct search.
Eg. Paralysis of auditory nerve
Hearing .Impaired, papralysis of auditory nerve from
Sensation as if fingers were thumb
Extr.Awkwardness, fingers
Gangrenous stomatitis
Gen. Cancerous affection, noma

3. INTERPRETATION OF RUBRICS
This method is mainly used for searching the rubric in the mind chapter. The symptoms or rubrics may not present in the direct form, the meaning of the symptom has to be understood in the contest of the case taking, and the suitable expression for that has to be found out in the repertory.
All the expression obtained on case taking is not found in the repertory, but the equivalent or allied expressions may be found through the interpretation. 
Eg. Complaints of nursing mothers
Generalities. Loss of fluids
Doubtfull
Mind. Irresolution
Anorexia nervosa
Mind. Eat refuses to

4. SYNONYMS 
Synonyms are rubrics without remedies referring to a rubric (master synonym ) which contain remedies.
The synonym rubrics are considered synonymous with the master synonym. The remedies & sub rubrics are added under master synonym. 
Eg. Mind. Cosmopolitan (Travel)
Mind. Exclamation (Shrieking)

5. CROSS REFERENCES
Cross references are rubric with remedies referring to other similar rubrics with remedies. The meaning is similar, but sufficiently different to legitimate a different rubric. Remedies and sub rubrics are added to the most appropriate rubric.
In this method the required rubric is selected by referring to the options provided at the rubric originally looked for.
#. Confirmatory cross reference
#. Comparative cross reference

a) Confirmatory cross reference.
An allied or similar meaning rubric is indicated in bracket against the rubric (primary rubric) which is originally searched  for which is having no medicines, but the medicines are present in the rubric that obtained after cross referencing (secondary rubric)
Eg. Mind.Abandoned
Medicines are indicated in Forsaken,so this medicines may be considered for Abandoned also.
Mind. Faultfinding (Censorious)

b) Comparative cross reference.
In this process, the cross reference is indicated in parenthesis against the primary rubric, medicines are also found against both in the primary & secondary.
This helps the physician to select most appropriate rubric in the given contest & to facilitate a wider choice of medicine.
Mind. Scorn & Contempt
Fear & Anxiety

6. SYNTHESIS OF RUBRICS
Synthesis of rubrics is combining two rubrics or more than two rubrics in a logical way to make one which is needed in the case but not found directly in the repertory.
may be either inductive or deductive.
Whenever a required symptom is not available in the necessary form two or more different rubrics may be brought together to arrive at the appropriate expression in the given contest. 

a) Combining two small rubrics
In this method two rubrics are combined which are not represented well or having only few medicines, we can consider all the medicines in both the rubrics to form a new rubric.
Also used when the modalities are not available in the required rubric.
Eg. Perspiration around neck
External throat. respiration
Back.Perspiration,cervical region.

b) Combining different rubrics
In certain condition / cases the required rubric is not available in the same form at the same place two or more different rubrics may be clubbed together to get a rubric representing the given condition / contest. The medicines which are common to the rubric may be considered as the medicines for the given condition.
Eg. Adenoids
Respiration. Snoring
Mouth.Open,sleep in
Throat.Inflamation tonsils r/c
Throat.Induration tonsils
Nose. Obstruction sleep in
Gen. Cold tendency to take

REFERENCES
Tiwari : Essentials of repertorisation
Munir Ahmed : Introduction to repertorisation
Dhawle : Principles & practice of Homoeopathy
Synthesis : Version 7
Mohanty : Text book of repertory.