Awesome. It's a So Cal staple that's as good here in the desert as it is on the shore.
I'm sure you've all heard about the secret menu, great shakes, etc. So I'll just tell you how I do it at In-N-Out, and I'll do it with the same skill as they do: I'll leave you wanting more.
DO NOT STUFF YOURSELF! I'm a big guy, and I usually get a cheeseburger animal style and a flying dutchman. Under $5 and the perfect amount. Believe me, the flavors are so potent it's easy to get carried away.
See what I mean; you want more, right? That's the secret sauce...