Check out what some celebrities wore at the recent 2014 Billboard Music Awards.

The 2014 Billboard Music Awards was held recently at the MGM Grand in Las Vegas, Nevada and saw a string of singers, rappers, musicians, bands, models, actors and er, Billy Ray Cyrus attending the event.

Jennifer Lopez, Pitbull and Brazilian singer Claudia Leitte kicked things off with a song called We Are One (Ole Ola), which is the World Cup 2014 theme. Before that, though, Lopez walked the red carpet with boyfriend Casper Smart in a familiar-looking outfit.

Wearing a sheer red Donna Karan dress – with flawless hair and makeup to boot – Lopez worked the look like the pro that she is. However, if you’ve been following J.Lo’s style and fashion “career”, you might remember her wearing a similar-looking green dress way back in 2000 that got a lot of negative attention.

Versace vs Donna Karan: Did Jennifer Lopez try to undo a fashion mistake made way back in 2000 with this sheer red dress?      

Don’t get us wrong, we love the updated Donna Karan version. We just wonder if Lopez would re-hash other old looks in the near future…

But back to the Billboard Awards. Here are some of our top looks and a handful of our “what-was-she/he-thinking” pictures from the event.

DON’T go all out and wear a gigantic chain around your neck (even if your name is 2 Chainz) to get attention. It’s bad for the neck and posture. DO go bare – on the face and body – like Nicki Minaj (but remember to stay classy, girls).

DON’T be like Charli XCX and wear your nasty-looking nightie out of the house. Also, a hairbrush/comb is one of life’s greatest grooming tools. Use it.

DO turn up polished and clean like Kesha, even though her look this time around did not really suit the event.

DO go easy on the makeup like Iggy Azalea.

DON’T be like this guy (Billy Ray Cyrus). EVER.

We sort of like this look on Kylie Jenner (she’s 16 so she can get away with that crazy hair), but DON’T wear laced-up shoes like these if you have big feet. Unless you actually want your feet to look bigger.

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