I work the 3rd as a security guard. If you have recently gotten a job working 3rd shift it will take some getting used to. Some people can get used to if right away and others it takes awhile. There's even a few people that will never be able to get used to it so they change shifts. Here are some tips on working the 3rd shift.
1. Make sure you get a full 8-9 hour sleep during the day. This may be difficult since the sun is up. Get some shades that will block the sun. This way you have a dark room to sleep in and you will sleep better.
2. During your shift limit your caffeine intake. You don't want to drink caffeine when your shift is almost over, you won't be able to sleep. Try drinking water throughout your shift. Its amazing at how much energy water gives you when your trying to stay awake.
3. Stay away from junk foods. Eating these will give you an energy burst and then you will crash a couple hours later. Try eating fruit as this will give you energy and no crash later. Make sure you eat enough as well.
4. Put your phone on silent. Don't let your friends who don't listen or telemarketers wake you up. Your friends and family should know that this is your time to sleep.
5. I recommend using a sunlamp especially in the fall and winter months
You will get very little sunlight and your body needs that for energy. Try a sunlamp 45 minutes a day. You can get them from amazon.com.
I hope you find these tips useful. Happy night shift!