Strategy- Firstly cover Thermodynamics completely with last 10 years gate papers and after that when you are through with the subject then its time for heat transfer and IC engine cycles i.e. Otto, and diesel cycles. With Thermodynamics it is easy for you to cover heat transfer and understand it easily. Now when you are done with these subjects then its time for Fluid and power plant subjects, comparatively fluid syllabus is more than power plant, power plant only includes vapour power cycle and steam power cycle. So these are the very important subjects Now the most important subject according to me is Production Technology, all last year exam gives you an idea how important is this. In GATE 2013 it consist of 16 marks out of 70. so it makes you feel that how important is this subject, so give sufficient time to this subject to justify its importance. In production technology metal cutting, casting, forming is very very important. Now subjects Theory of Machines and Strength of Materials have equal importance. Always 7 to 8 marks is expected from these subjects. Machine design and RAC consist of less marks but never underestimate these subjects as of their importance. According to me at least 20 to 25 days are requires for the practise after your preparation of all subjects. other subject i.e. maths, Eng. and aptitude also require time for the practise. HOW TO MAKE PREPARATION SIMPLE- Now you are thinking all these subjects done at a time is very difficult to remember. so here the some ways to how to do this: Firstly you prepare thermal subjects i.e. Thermodynamics, heat transfer, IC engines. then start fluid along with practise of previous subjects. at the middle of fluid start production and When fluid ends along with of production start some 1 or 2 hour practise of maths, and aptitude. When you all are done then try to give some tests so that to increase your speed. doing all your practise set a time alarm near to you so that every time you can increase your speed. Now for machine design and rac if more time is there then go completely through these subjects but if time is not there then try to see last year papers what is they are asking in these subjects and make Strong that topics. 20 to 25 days of complete practise is must. Try to maintain daily 8 to 10 hours, is you are able to give more that is up to you Hope this helps!!!