I know I have not done one in a while, but now I will!
Dos (There is only one of them):
Do make a show like Survivor, and Big Brother interactive- One time I joined a Survivor show, and I completely forgot about it. Luckily, it doesn't matter, because it wasn't interactive. The creator just made everything up! I think that is unfair because people couldn't campaign for votes, so make it interactive. Use e-mails and stuff like that to make interactive.
Don't submit a celebrity, or a real-life "veteran" on the show- Do you know how bad of a target that will make you? Let me give you examples (sorry for spoilers)! Jimmy Johnson, a NFL football coach, was on Survivor: Nicaragua! Due to his celebrity status, his tribe went against him, and he became the 2nd person voted out of his tribe. And in Big Brother 13, they have 6 returning "duos" that have played this game before, and the house went against them in day 1! However, let's say that you want a Big Brother winner on the Mole! That will be acceptable since the house can not really vote you out. Also, it may be easier for reality show hosts as not everybody knows every celebrity nor they watch every show.
Don't leave the show on hiatus without leaving a note- You do not how many people will forget about the show. Trust me that happened to one show I was in, but if a certain fellow haven't e-mail something about it, I would totally forget that show. It is like a famous twitter person left twitter without any note. That person will lose a bunch of followers if he or she did that!
Don't be a sore loser- If you lose, don't be a sore loser! There is plenty other reality shows than that reality show. Plus, there is a high chance you can come back. I hate sore losers in real life, and that is the reason why I hate Jeff from Big Brother! Little old cat ladies gave him 25,000 dollars which I pretty pissed about.