Dear student. 

Greetings. 

He first step is remembering the formulae correctly. Most students are able to solve the series resistance problems easily and have a hard time solving the parallel resistance problems. The key to solving the parallel resistance problems is to proceed the solution in such a way that at last, you're left with a straight line of circuit with resistances in series combination. This is the easiest way to solve resistance problems. 

Thank you. 

I hope this helps. 

Solve many Problems, This will improve Your Problem-solving ability and will reduce the time to analyse the Problems If You are in class 12th then I don't recommend You to spend too much time on solving complicated circuits Because this type of questions can be made too complicated and there is nothing useful to solve so many Problems because this type of Problems are generally not asked in the exams , Problems On circuits are conceptual In Nature rather than long and complicated.

Hello Chiranjeevi ,thanks for asking this question on this platform.firstly try to get a clear idea about any electrical element like resistor opposes the flow of current and then learn basic rule like kvl and kcl for this you can refer any good book and according to me you should follow fundamental network analysis by Charles alexendar this will really help you to clear your idea about any circuit .thanks