Evaluation agreements. Most people in your position use evaluation or option agreements with potential licensees. These agreements allow someone to evaluate the potential, and if they like your stuff, to make a deal. If your application has not been published you will need a nondisclosure agrement (or some variation) as well.
License agreements. Because there is always a possibility that a patent will not issue many people in your position enter into licenses with a two-tiered royalty. (Here is some basic invention licensing information). If the patent issues, you receive one royalty; if the patent does not issue, you would be entitled to a lower royalty. There are numerous ways these agreements can play out and we've outlined a few of the scenarios in one of our books.