Include an abbreviations section.
Bonus tip: Make sure it includes all of the abbreviations that you actually use in the pattern, and none that you don't use!
I've been editing for a while now, and have read through hundreds of patterns looking for errors. This is right up there as one of the most obvious beginner mistakes. I admit that in my own free patterns (which have not, by the way, been edited) I don't have abbreviations!