Legal Question in Business Law in Oregon

You do not absolutely need any contracts, but you would be better of having one. The operator of the restaurant needs to pay you for your work, perhaps as an employee or as an independent contractor. If you are to be an employee of the restaurant, you should have an employment agreement that spells out your tasks, your pay, when you get paid, grounds for termination, and the like.

If you are an independent contractor (dancing at various locations), you should develop your own contract for services, which states your tasks, the conditions that the establishment must maintain (no abusive drunks, etc.), whether your shows can be rescheduled without notice, how much you are paid and when. Without a written contract, the restaurant operator might refuse to pay you, saying that you were just dancing for free because you like to dance or because you were advertising your services.