Which PSU you are in.
Count on your factors which are:
GRE Score, TOEFL etc., education loan or scholarship chances.
Start with these exams and get scores.
Applying to places has no harm but it depends on various other factors like how essential current job is to you and family. If not a problem, go ahead with a sincere PhD program from a good university based on your preference of subjects and research areas.
IVY league colleges, Univ of California - Berkeley & others, Wisconsin, RPU, Stanford, Columbia - make a list based on your score and subject.
A good coaching center may help you with SOP writing and other procedures.
Khushboo AR, Proud Indian national.
Source: Quora Digest