Landlords should use an application process. This way you can check references, you'll know where they work, how much they make ad you'll be able to talk to previous landlords. FWIW, many tenants with pets are willing to pay more because many landlords do not allow pets. Once again, talk to previous landlords about the pets and any potential bad habits that these pets may have. The bad news is that many decent tenants are just trying to get on their feet so they can purchase their own home. They'll be with you for a few years and then out the door they go. At the same time, these are probably some of the best tenants you can get when it comes to taking care of your investment and making payments on time.
There are books available for this sort of thing, the do's and don'ts for landlords. Check you local library.
Oh, and I almost forgot, get to know you state and local laws regarding rental properties, landlord rights and tenant rights.
You may also have to have the house inspected prior to renting it out. Local codes may require certain things that a non-rental property doesn't need (bathroom ventilation, smoke detectors, fire extinguishers, GFI's, etc...) This varies on a state by state, or even commnity basis.