[Xenalyte]

The best way I ever found to tip was to estimate what you will spend and put 20% of that on the table. When the wait staff comes over you tell them that is their tip. Anytime you have to look for them to get something, 1% of the money goes back in your pocket. Normally they are not offended and you do get them to stop by your table more than others asking if everything is all right.

Never been a waiter, have you?

When I was waiting tables, I would have been quite offended, and I would have pointed out your table to the rest of the waitstaff.

[Just another Joe]

Never been a waiter, have you?

Nope, been a bartender though. Works on the same principle.
I've had very few wait staff offended by this, and I will sincerely ask them to please let me know if they are.
The reason that I ask is so that if even a large minority are/have been offended by it I would stop doing it.
I really don't want to tick off the people that make and serve my food.