Trying to get served at a bar anywhere can be frustrating and it can be even worse in a packed bar in Las Vegas. So we've compiled some guidelines to get, and keep, the bartenders attention.
Getting Attention
1. Send hottest person in your group

Lets face it, if you're friends with Robert Pattinson, he should be buying drinks to begin with.
As a general rule of thumb, girls will get better service from guy bartenders and vice versa. Guys notice hot girls, so make the most of it. A double take means you've gotten twice as much face time as anyone else who's only getting a single glance.
2. Eye contactKeep an eye on the bartender and make eye contact. But that doesn't mean stare them down or scowl at them! Try and look friendly.
3. Have cash or card out and ready
This man is clearly over compensating for something, I'm guessing inflation.
Bartenders tend to notice two things: money and hot people. If you've got both, you should be good! If you've only got money, have it out (but don't be obnoxious about it).
4. Have a good spot at the barNot all of the counter at bar is created equal. Some places have awful visibility, making you invisible to the bartenders. If you're waiting and everyone around you is getting served but you're not, move over one way. Feel free to defend your spot at the bar, but don't be "that guy" who blocks a huge section off just to drink.