GATE

It is very good that you start your preparation right from the first year of college. Two years of rigorous study have paid off, and you very well deserve a break. Studies include basics of every branch. Just observe everything, and make sure you want to get into technical side, i.e GATE / ESE. Second year usually has some important subjects, make sure you don't study them just for clearing the semesters, but for getting in depth knowledge. It is very tough to do that, but once you do that, it will pay you off very well 2 years later. In the 3rd year, join a coaching. Or, arrange some good study material and start serious preparations. You won't get that much time in final year, plus a head start is always better. In the final year, revise and repeat. Infinite times. Join a few good test series. Attempt all tests. You will gain the momentum that will surely help you perform well on the day.

Power electronics - P. S. Bhimhra
Power system - Nagrath kothari
Electrical machines - P. S. Bhimra
Networks - Valkenburg (Madeeasy notes are sufficient)
Control system - Madeeasy notes (B. S. make, nagrath kothari)
Analog - Bolyested
Signal and system - Madeeasy notes
Op-amp, filters etc. - D. Roy Chaudary
Digital - Anand Kumar
EMT - saiduku
Measurement -madeeasy notes
Engineering mathematics - Ace academy and Madeeasy notes (I followed H. C. Taneja for some part). For questions - Madeeasy book containing previous year questions and R. K. Kanodia
Apart from these I will recommend you to follow Madeeasy handwritten notes. They are extremely helpful and will help you in identifying portion related to syllabus. NPTEL videos are another best source for getting your doubt clear if you are preparing your own. Best of luck!

You have two option before you start, either to prepare your own or take coaching. Now according to me first one is the best. Coaching will be helpful only when your basic are not at all clear. First download the syllabus and then start preparing. You can refer to the following books:
Power electronics - P. S. Bhimhra
Power system - Nagrath kothari
Electrical machines - P. S. Bhimra
Networks - Valkenburg (Madeeasy notes are sufficient)
Control system - Madeeasy notes (B. S. make, nagrath kothari)
Analog - Bolyested
Signal and system - Madeeasy notes
Op-amp, filters etc. - D. Roy Chaudary
Digital - Anand Kumar
EMT - saiduku
Measurement -madeeasy notes
Engineering mathematics - Ace academy and Madeeasy notes (I followed H. C. Taneja for some part). For questions - Madeeasy book containing previous year questions and R. K. Kanodia
Apart from these I will recommend you to follow Madeeasy handwritten notes. They are extremely helpful and will help you in identifying portion related to syllabus. NPTEL videos are another best source for getting your doubt clear if you are preparing your own. Best of luck!

One Year and 4 hours daily is more then sufficient to prepare for the GATE. In the beigning select your weak and strong topics. Start from your strong topics as you need motivation in the beginning. So cover your strong subjects first then gradually move to the other subjects. Solve questions regularly. Be carefull while choosing the study material for the GATE. Do not be misguided for best books of GATE. Your text books of college are more then enough for the preparation and also no single book is sufficient for a subject. For basic understanding of subject go through the books you studied in your college, and if you have any doubt go through video lectures of NPTEL. Prepare your notes regularly (especially from nptel)
For precise syllabus and basic points of subjects go through handwritten notes of made easy Delhi also available online at www*mbgb*. Co MBGB. CO the notes contain various tips and trics to solve questions in minimum time. Please remember regular practice is must for GATE. So solve as much as question, if you found some topic to be tough to understand then see some solved question related to that topic this will eventually make things easier. Notes of made easy and personal (not through quora fb) guidance from some one successfully cleared GATE is strongly advised.