Here are my simple directions for doing a In n Out run.
Make your way to Terminal 1.
Walk east on sidewalk ( away from the airport, towards the rising sun, or with the setting sun to your back)
Cross one airport road at traffic signal, then cross Sepulveda Blvd at traffic signal.
Turn left on sidewalk and walk north till you see a tattoo parlor on your right.
Cross Sepulveda Blvd at cross walk.
Enter In N Out and order burger.
Rinse and Repeat.
HP