USA

Hi
Follow these:
1. Choose which Masters u plan to do and search about the universities providing that particular course. Shortlist atleast 5 as per Your preference of place, budget, scholarships etc.
2. For MBA you need GMAT and for other master's its GRE, which are the standardized tests accepted in almost all the universities in USA. In addition to this, they ask for english language proficiency thru TOEFL/IELTS. High score will get you a good university.
3. Most of the universities ask for work experience of 2/3 years so take references from your employer/s. If you have no experience, then choose universities accordingly. There are very few who offer you master's w/o experience.
4. You also need to write SOP (statement of purpose) or Personal statement. The guidelines for the same can be found on respective universities website.
5. You also need to see the financial aspect as master's costs you somewhere between 50k$ to 70k$, so loan application should be processed immediately after u get test scores.
If you are good in research, you may write a good research proposal to get GA/TA or grants for your integrated P.hd.
Hope this suffice. Feel free to revert for any more queries.

Dear Kunal, the question you have asked is very interesting & I am sure everyone knows the answer - If its Automobile it should be Germany as that is the place with lots of opportunities & education too is free of cost. The number of universities is not that large thus you need strong Academics & high GRE scores to get accepted in German Universities besides knowing up to 2-3 levels of German. You have good courses for Mechanical too at German Universities.
While US has no dearth of opportunities & the number of Universities is largest, you need high/decent GRE to have a university & grab a couple of Aids/Scholarships for the courses both in Mechanical & Automobile. The choice is yours as the distance, climate, culture & cost differs in USA & Germany & the post study stay is 2-3 yrs & 1yr in respective countries.