other ideas are
compile a list of the type of silly mistakes you tend to make
and recheck your test answers to see if you did them again
be well rested before a test, plenty of sleep, so you're wide awake
maybe a little coffee,coke, caffeine or a slight sugar high as well
practice the type of questions you often miss or make silly mistakes on
just prior to the test, or many times prior to the test
do practice tests, if available, or review problems if the instructor provides or the computer program provides them
on the test reread the problem to make sure you understood it, and aren't answering a slightly different problem by mistake. sometimes it's sort of an optical illusion as you see what you're expecting to see, since you worked a similar problem before, but slightly different.
recheck your answers, hopefully the test isn't such time pressure that you have time to recheck
do the easy questions first, save the hardest for last,so if it is time pressure you at least will get the easier questions right. if time pressure guess at the hardest questions at first, so you have an answer submitted, then go back and try to solve them the usual method.
if there's time, work each problem by 2 different methods, such as algebraically and then graphically. Have a graghing calculator such as a TI83 or 84, if allowed.
read the instructions on required format. often people put in fractional form when the problem required a decimal answer, and required a decimal answer rounded to 3 places and you do 1, 2, 4 or more
the format required may change by each question, throwing you off, so pay attention to what's required. It's sometimes almost like the Simon Says child's game, and it can cost you major points
check and recheck your answers 2,3 or more times. Never turn in the test early, use every second down to the last second. be careful though correcting an answer, as some people change a correct answer to an incorrect one, so recheck those at least one more time, until you see the mistake you made on one of the 1st 2 tries.
pace yourself, check the time, so you don't unexpectedly run out of time.
don't do anything suspicious so you don't get an F for cheating, as they often have rules you may not have noticed, violate a rule like that and a red flag goes up to the teacher, proctor or the computer watching you on zoom