Know what you are doing! Don't go into dealing with the infernal half assed. Have all your wits about you.
Lose any religious symbology in the room, it irritates them.
Do your summoning some place boring, a science class room works great!
Draw your floor symbol well, artistry counts people.
Have a well thought out contract. Be certain of the fine print.
Be prepared for the double cross, its' kind of what they do.
Have a holy water filled water balloon. It can seriously fuck their world up, plus it is kind of halarious.
Don't go with black robes, that is always a bad choice. Shorts and a comfy t-shirt is probably a better move.
Don't do a sacrifice, that's just tacky.
