Instances where you do not have to tip
In case, you are not happy with the service; you do not need to tip at all. In case, the porter, bartender or the waiter was rude, or the food served to you is cold, etc., you do not have to tip him or her. If you are not happy with the service, do not hesitate to inform the manager. Tell him or her the reason why you are not happy. Some restaurants even give you a free meal if you are not happy with the service.
Always be ready
The USA is the only nation that has $1 notes while the rest of the globe has moved on to $1 coins. When you are in the USA, ensure you have many $1 notes in your purse or wallet. If you are sitting in the lobby of your hotel and you only have $20 notes with you, do not feel shy to ask the porter for change. He will give you back the change willingly.
In the USA, as a traveler, you will visit many places by yourself or with your family or friends. You may go to museums, galleries, national parks, etc. If you have an interest in horse racing like the ones you see on the TVG site, you may need to travel to these places by car. Remember to tip the driver. They expect you to give a 10-20% tip.
Tipping tour guides
When you are in the USA and go on guided tours of historical places, celebrity homes, etc. with the tour guide doing a good job, give him or her 5 to 10 dollars.
What about bars?
When you are drinking at a bar, the general rule for tipping is one dollar for a drink. This also applies when you get up from your seat and order a drink. Here again, the bartender expects a tip from you. The common norm is to tip at least two $1 note bills to the bartender.