I like to be straight up with the girl. At the beginning of the date I tell her, "Look, lady (sometimes I use their name), if this date is going to be enjoyable for both of us, I'm going to expect you to pay for everything. In return, I will entertain you all night with comedy and magic. If this doesn't sit well with you, there's the door (and I point to the door of the diner)."
Oh, whenever I go on a date, I ALWAYS meet them at the local diner by my house, by the way. I think it sets a good tone for the evening, and there is always some serious strange in there in case my "date" doesn't take my offer.