@Lauramay0 Basically, in addition to probably no smoking no pets and no parties, the things that you want the guests to do, or what will help protect you.
So, for example, we have added over time that there are no visitors allowed on the property that are not part of the guest reservation without our prior permission, a lot of people have 'quiet hours' at night, we have that guests are expected to recycle, wash their dishes and tell us of any damage they do or anything not working, I can't remember we may have it also that they are expected to turn off window AC in the summer. If you aren't on site, you probably want more rules, or if you have more amenities, like a pool or fireplace, you would add whatever 'rules' about that which were important.
You can also put in the rules that if the guest breaks X rule, you will charge them X $$, this is not necessarily going to be enforced by airbnb, but it is at least a better place to start and might help prevent problems.
Hope that helps.