My biggest tips would be:
- getting access to high quality questions that are “retired” or considered close to the real thing (probably will have to pay for access)
- make sure you understand how the test works (types of question and topics included, time constraints, is it via a computer, etc.)
- do lots and lots and lots of practice questions (best thing that raised my score when I retook the LSAT). Seriously, do tons of them.
- take practice tests, timed, and if possible using the same system / interface as the real thing (the GRE people may share a few practice tests…if so, definitely use them!)
- if you have the cash don’t be afraid to pay for a system (Kaplan, etc. no idea what systems are best for thr GRE…you may need to search on Google, Reddit, etc to get previous test takers’ reviews). You will probably have to pay to get access to quality practice questions. You may be able to find just question sets for sale online which could be cheaper than buying a whole practice system. It’s up to you. But if the test is important for getting accepted to a solid program then it maybe worth investing in a good program.

Good luck!