NO watches in the testing room. I would recommend that you try not to get used to using your watch in that way b/c you will not be able to do this on test day. There will be a small timer on the top right of the screen that you can hide or keep it showing. It will start at 75 min and work down to 0. This will be your only clock on the computer and in the testing room. I recommend that you start getting a better feeling for what two minutes "feels" like. Also, it does not make sense to start you Gshock every two minutes... even if this only took 2 seconds to set it for all 37 questions, you'd be waisting over 1 minute which is valuable time.
This also includes writing A, B, C, D, E on your scratcpad every time (if you do this). Writing down ABCDE will also cost you 1-3 minutes on test day in each section. NOT WORTH IT. Just put lit dashes, or 5 dots, this will take .5 seconds and save enough time for a whole extra question.
Time is the most precious thing you have the test, and the better you get at feeling the time, knowing the time, and understanding the time, the better you can use every last second of it.
GOOD LUCK!