Hi

You can prepare for SSC CGL examination with the help of a coaching or by self study on your own.

If by sources you mean the books you should follow for SSC CGL then you should use the following books as your source of preparation for SSC CGL:-

QUANTITATIVE APTITUDE

*Elementary & Advanced Mathematics: Kiran Prakashan

*Advance maths for General Competitions: Rakesh Yadav/KD Publications

GENERAL INTELLIGENCE & REASONING

*Verbal and non-verbal reasoning: R. S. Aggarwal

*Analytical Reasoning: M. K. Pandey

GENERAL AWARENESS

*General Knowledge: Dr Binary Karn /Lucent

*Manorama Yearbook

*Also read newspaper for current affairs

ENGLISH COMPREHENSION

*a mirror of Common Errors: Dr Ashok Kumar /Academic and test publication

*Competitive General English: Kiran Prakashan

*Objective General English: S. P. Bakshi

For details go through

https://competition.careers360.com/articles/ ssc -cgl-books

Also follow the below tips

* make a routine, and strictly follow it ,give more time to your weak areas in your routine . Routine will be very helpful for you as it will help you to study in a systematic way and avoid wastage of time and procrastination

* Prepare short notes :- you should prepare subjectwise short notes , it will help you a lot during your revision for your exam

* Revise :- the syllabus of SSC CGL is wide so revision is must otherwise you may not be able to recall  what all you have studied during your exam

*Practice mock test papers:- it will help you to understand the examination pattern, types and difficulty level  of questions which are asked in exam,  you will also get to know your preparation level and then can work on your weak areas to perform well in your examination.

For detailed information go through

https://competition.careers360.com/articles/how-to-prepare-for- ssc -cgl/amp

Thank you