Please help!

[Cornflower MM]

Alright y'all, this is serious. I need tips on acting extremely happy, sassy, and confident.
I'm not particularly good at all three, and my company dance requires all of the above, done well, and LOTS of it. PLEASE HELP ME!!!!!

[Søren]

Happy: Smile and laugh when other laugh. Best sport to seem happy. Think about positive things if you need to make the grin appear.
Sassy: Look up Gerard Way
Confident: Just don't doubt yourself. Don't think about things that you have doubts about. Just focus on what you know and what you're good at. Confidence will come naturally.

[Cornflower MM]

THANK YOU.

[Rosie Willowwater]

I act confident when I try and act like myself, not trying to be someone else to make others happy.

[Wylder Treejumper]

Heh, some of those are easy. There's only one trick to being confident: always pretend you know what you're talking about, even if you can't tell whether the words coming out of your mouth are even complete sentences. Often, the people that are the most confident are often the ones who have absolutely no idea what they are doing, but they are either too dumb to know (mostly kids at school) or have too much to lose to let on (politicians).

As for being happy, eh, fake it 'till you make it. Laugh and smile and you'll feel happy faster than waiting to be happy before smiling and laughing. Scientifically proven.

[Cornflower MM]

It's a little hard to convey those in a dance, but thanks! It does help!

[Hickory]

Learn stuff. the less you know the more you think you know.

[Cornflower MM]

That works.

[Banya]

For confidence, take up space. People who stand near the corners of a room, tuck their hands into their sleeves, sit and pull their knees to their chest, etc. are usually the insecure ones. Confident people spread themselves out because they know they belong there. Don't have a worried look on your face or continuously look at others, no matter how you actually feel. And don't continuously mess with your hair; it's one way teachers distinguish needy, childish female students from the more mature ones.

For happy, be quick to smile broadly and laugh, as others have said. But laugh with confidence - I don't really know how to describe it, but there are followers who laugh timidly and people who laugh because the world can't stop them. I guess, when I think about it, don't look at people too much while you laugh, because it gives the impression you're just following. It's weird how many little rules like this there are that you easily notice but don't really think about.

And for sassy, your brand of sassy is completely your own. To me, it's being challenging in a friendly way.