New to Wholesaling

[Emory Prior]

I understand the concept of wholesaling, and I've found a property I want to go after and find a buyer for. Though I'm struggling with understanding the contract that I'll be signing that gives me legal ownership of the house. I know that the contract I'll use to give over the deed to the cash buyer is the Assignment agreement, but what's the contract I sign when I found a house and want to take steps to secure it? 

Also is it ok for me to sign a contract for a house and then just wait like a week before finding a buyer? I currently don't have a buyers list or even know how to get started with that but I found a foreclosure house with a great location that I think would interest some investors.