Use Tip Trays with Credit Card Insignia
Although it is not clear why, research has found that simply seeing credit card insignias increases guests’ willingness to spend money. It is easier to spend more now with a credit card and pay later than it is to part with the cold hard cash in your pocket.
If your restaurant does not use tip trays or check presenters with the credit card logos, have your manager order them. Most credit card companies will provide these free of charge. Convince them that guests will spend more when they see that they can use a credit card.