Cornell University's Center for Hospitality Research has conducted several studies revealing some interesting facts about server habits that can boost tip percentages. Here are a few of them:

Touching - Waiters experienced a tip increase from 11.8% to 14.8% of the check total when they briefly touched the shoulder of the customer. . .

Squatting - Two studies showed that waiters who squatted next to the table when taking orders and talking with customers increased their tips from 14.9% of the bill to 17.5% of the bill in one study. . .

Giving candy - A study that involved giving customers a piece of candy with their bill showed an increase in tip percentage from 15.1% to 17.8.

Being helpful - A study of hotel bellmen revealed that just taking a few extra minutes explaining to guests how to operate the television and thermostat, opening the drapes for guests, and offering to fill the ice bucket increased tips from $2.40 to $4.77.

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