As a server, I've had really great tips and really crappy tips, often in the same night. It seems that some people simply weren't informed on how to tip. I've come up with a list of who to tip and how much to give. (Now none of you have an excuse to claim ignorance on tipping protocol.) When tipping, don't forget that the person receiving the tip is doing you a service and is taking the time out of his or her day to assist you.

Servers should receive 15% of the bill at the very least. I have rarely seen instances where anything less than 15% is merited or acceptable. If there were few to no complaints, 20% is standard. Anything less suggests that there was something wrong with the service. In some cases, such as with difficult orders, outstanding service, or time-consuming needs, 25% would be a more appropriate tip. Also remember that servers should not be punished for things beyond their control such as poor quality of food or kitchen wait times.

We don't often forget about tipping our servers, but don't leave your bartender out in the cold, either! Bartenders typically make less than minimum wage as well as servers. As a general rule, tip $1 to $2 per drink. When purchasing wine and receiving wine service, 10% is standard.

Delivery drivers should receive $2 at a minimum. For delivery, 15% is fairly standard, but 20% is appropriate for outstanding service. Delivery drivers offer you the convenience of eating prepared food without leaving the house. Without them, you'd have to leave your house to get that pizza.

Tattoo artists are often overlooked when it comes to tipping. Remember that they are creating art for you. Tattoo artists should always be tipped at least 15% of the tattoo cost, but, like serving, 18% to 20% is standard. This also applies to piercing artists!

Taxi and Uber drivers should be tipped as well. Remember all those times that these drivers took you and your drunk friends home safely or transported you from Point A to Point B in a huge, unfamiliar city? Thank them for the safe trip by giving them $1 at the very minimum. Also be sure to add $1 to $2 for every bag they help you store.

Many people may not think of it, but housekeepers should be left $2 to $5 per night. I would even go so far as to say that each person in the room should leave $2 per night, because the mess is typically bigger with more people. Housekeepers work hard to provide a clean place to stay, and I think that plugged toilet and dirty carpet are worth two of your dollars.

Stylists should also be tipped about 20%. They work hard to make sure that you are satisfied with the final product. I originally wrote "hair stylists," but it goes beyond that. Tip those who clean up your eyebrows, paint your nails, or style your hair.

Valet drivers should typically be tipped $2 to $5. This is yet another service that is provided for convenience and should be treated as so.

Movers who drag all of your furniture around and arrange it the way you want it deserve to receive a tip, even if they're not the first people who come to mind when the word "tip" is brought up. Generally, 5% of the total moving bill is appropriate. This 5% tip would be split between all movers involved.

Lastly, if you can't afford to leave a tip, you should reconsider your decision to pay for services such as the ones listed above.