Cartoon Invoices

I've gotten a couple of emails asking how to invoice, what IS an invoice, etc.So, let's take a chapter from the ol' MIKE LYNCH COLLEGE OF CARTOON KNOWLEDGE.It's great when you get that letter, email or phone call letting you know that you sold a cartoon. A lot of the time, when I'm home with a snoozing cat next to me, drawing, I can only wonder, "Are these funny? Funny enough to SELL?!"A