Guilty of fake-n-baken! My advice to you...go in a regular bed the first time for 8 minutes maximum (since you said you burn easily). Skip the next day to give your body a break. The following day, jump up to 10 minutes. Basically, go every other day, and add 2 minutes onto your time...ONLY if you haven't burned!!! Do not use outside sunscreen because outside rays are UV...and indoor tanning lights are mainly UB rays. Instead, use an indoor tanning lotion...this should help prevent burning. I would ask the person behind the counter which type of lotion would work best for you (tell her what you mentioned here). As far as what to wear, most people usually go naked, but it's not wrong to wear a bathing suit bottom or underware when you go in. Whatever makes you feel comfortable. Oh yeah, when I go, I usually only expose my face for half of the time in the bed. The other half I have it covered so I don't get all red!
Hope this helps! Good luck
Edited to add: get in the habit of applying body lotion as soon as you get out of the shower if you are tanning. First, it retains your tan longer and it also helps to reduce the leather looking skin that some people start to obtain!