As it stands now, the federal government allows business owners to pay their employees who receive tips as low as $2.13 per hour. Not every state pays their workers that low, but 17 of them still do.

Flickr/Susanne Nilsson - flic.kr

As for the rest? Twenty-six states require business owners to pay their tipped employees higher than the federal tipped minimum wage, but still lower than minimum wage. And there are seven states — California, Oregon, Washington, Nevada, Montana, Minnesota, and Alaska — that require business owners to pay their tipped employees the state minimum wage (which, as we all know, isn't that much to begin with anyway at just $7.25 per hour).

So why do waiters and waitresses get paid so low? It's simple: They're expected to make up cash shortages with tips. In fact, tips are responsible for 85 percent to 100 percent of the average U.S. waiter’s income.

Still, the whole practice of tipping stinks. It's unreliable, even at the best restaurants. This is why restaurants across the country are doing away with tips altogether.

Regardless, many servers still have to figure out how to get by on an incredibly low guaranteed wage. That being the case, they need to do everything within their power to coax their customers into reaching deep into their wallets when it comes time to tip.

So, beyond raising wages, how can a waiter or waitress rake in more dough?

First, some obvious tips:

• Introduce yourself.
• Smile.
• Anticipate the needs of your customers.
• Know the menu inside and out so you can make great recommendations.
• Have the check ready the moment it’s requested.

There are other less obvious factors that affect a server's tips and might impact a decision to add a few more dollars in gratuity. Here are a few:

1. Dress the part.

First things first: Would you feel inclined to tip your waiter well if it looked like he was wearing clothes that hadn’t been washed in weeks? Probably not. So make sure you look presentable. Keep your fingernails clean. Keep tabs on your appearance over the course of your shift. Make sure there aren't any stains on your clothing.

You’re serving food to people who are hungry. Don’t let your degenerate appearance kill their appetites. They won’t tip you at all if they don’t rack up a bill because they’re repulsed.

2. The weather has an impact.

If you’re working a Saturday dinner shift during a snowstorm, you probably won’t make as much money as you’d make if the roads were clear. When the weather takes a turn for the worse, restaurant sales suffer.

3. Hair matters.

Another example of the patriarchy? Studies show that a waitress’ physical appearance affects tips, while customers don’t really care how their waiter looks, so long as he’s presentable.

Fortunately, there’s a relatively quick fix: Waitresses that wear something in their hair — e.g., a flower or a barrette — receive bigger tips than those that don’t. Believe it or not, a study revealed waitresses' tips increase as much as 17 percent from this little trick.

4. Touch your customers lightly.

Touch is a very powerful sense. When someone touches us, we feel warm and comfortable.

Perhaps not surprisingly, research indicates waiters and waitresses who touch their customers slightly get tipped more. In fact, when women are touched by an attractive waitress, they’ll tip an average of 44 percent more. Men will tip more too, but not as much.

It’s worth reemphasizing the word “slightly” in the preceding paragraph. Once you cross the arbitrary boundary and touch a customer “too much,” your tip will likely decrease exponentially.

5. Move to a city in the Northeast.

Where you wait tables geographically plays a role in your compensation as well. Studies have shown that folks tip the best in the Northeast and the worst in the South. Urban diners are also likely to tip more than their more rural counterparts.

6. Learn the art of up-selling.

No matter where you work and what you look like, all waiters and waitresses can haul in more tips by mastering the art of up-selling.

To do this, you need to be able to read people well, and you also need to be able to provide useful suggestions in a timely manner. Know your wine and entrée pairings. Suggest coffee and dessert after it looks like your customers are finishing their meal, and be specific with what you have to offer.

Alcohol is great for up-selling opportunities. When cocktails are ordered, always assume the customer wants a more expensive liquor — but ask before you pour it.

If, for example, a customer orders bourbon, find out whether the individual would prefer Knob Creek or Jim Beam. Hopefully they’ll choose the former, and their bill will inch up a little higher, which bodes well for your tip.

7. Use a tip tray with a credit card insignia.

Do the tip trays your restaurant uses have credit card insignias on them? If not, it’s time to ask your manager to swap the old ones out and get some fresh Visa- or Amex-branded tip trays.

Researchers uncovered a link between the appearance of credit card logos and insignias on tip trays and higher tips. Branded tip trays should net you 25 percent more tips.