Tip wisely:
Tipping depends on your own financial state. Tipping generously is okay, but you shouldn’t think giving away a fortune just to pay for good service, if that amount burns a hole in your pocket.
Pre-tax or post-tax:
Custom says tips are calculated pre-tax, but many people just use the total bill either for the sake of simplicity. If you are in a situation where the tip is automatically added in, it should be pre-tax.
Decide the tipping amount:
Figure out the kind of service you’re receiving. Some services should receive percentage-based tips, while others get a flat cost. A car washer, coat checker or furniture mover should be given a flat rate. Hairstylists or waiters should be ideally given 15-20 per cent, or more, if they have gone that extra mile to help you. Pizza delivery service is usually about 10 percent.
Use your best judgment:
What’s the real different between, say, 15 per cent and 20 per cent? The additional amount tells them how they’re doing.
Be discreet:
{{/usCountry}}Be discreet:
{{/usCountry}} Don’t flaunt while you’re tipping someone at a restaurant by leaving the bill in plain view. If you’re paying for a household service, placing the tip in an envelope is a good idea. Basically, you want to keep the tip transaction — good or bad — between you and the person receiving the tip.
-ehow.com