i went through this every time i was in school (had to work). first of all, when you find yourself sitting down and getting drowsy, get up and start moving around! especially if you are at work. most jobs i had someone could be fired for being found sleeping on the job. i worked as an aide when i was in nursing school
the first time and i was an rn when i went back for my bsn. i would get up and make rounds on patients or start cleaning up around the nurse's station. if you are working in a patient care facility there is always something that needs to be done. i was known to take nodoz, particularly an hour before tests and before getting in my car to drive. vivarin is just a double dose of nodoz. the hardest for me was sitting in classrooms after working a night shift and having a morning clinical. i sat with friends and asked them to "elbow" me if they ever saw me nodding off to sleep. i also compared my class notes against theirs to make sure i had gotten everything from the class. instead of lunch breaks i took short naps and had friends wake me up. i ate on the run--things like fruit, which is better for you anyway. then, when i got home i died and went to sleep. if i had to get up at a certain time, i had three alarm clocks i set to go off, never at the same time--staggered time in case i turned one off and went back to sleep. one of them, my treasured mickey mouse alarm clock that ran on batteries, rang very
loudly for an hour if not turned off. i kept each alarm clock more than an arms-length and more away from me and at different locations forcing me to have to get up to turn them off. i also was known to drink a large quantity of fluids before sleeping to assure i'd have to get up. that, however, didn't always work as i'd planned because i was often a bit dehydrated from my day to begin with!
i had remembered reading about thomas edison and how he never really slept, but napped all the time. he swore by it and lived his entire lifetime that way. one of his employers was so angry at all the napping that he did that he ordered him to send a telegraph message to him at regular intervals to prove that he was awake and doing his job. one of his inventions involved an automated telegraph message that was sent to his boss at regular intervals so his boss could be assured he wasn't sleeping on the job while old tom was slumbering away! very ingenious man.