Warm Up
Leave an extra few minutes early for your dance lessons and give yourself some time before class to warm up your bodies if its been cold outside. Dance injuries happen usually from the muscles not being warm before using them. It happens more easily then you think!

Footwork
Footwork is one of the cornerstones of good ballroom dancing - but it doesn't mean only learning the steps, it's also where your feet go and in what manner. One of the coolest things appearance-wise to learn is to dance with one's feet together instead of apart. Your feet should actually lightly brush against one another as they move. This means you have to develop a good sense of balance, because -- let's face it -- it's always easier to balance standing and moving with your feet apart. GFV

Kicksteps
Kicksteps -- whatever dance you're doing, try not to kick with your toes up. This is good if you're doing Country Western dancing, but for Ballroom, try to point your toes down and to the outside. It looks better. GFV

Beginner Dancer's Tip
Try never to refuse a dance with someone who is asking you. It doesn't feel very good to be rejected. This tip is for the ladies and the gentlemen, and a reminder to the Int/Adv dancers as well. This is how we learn to be better dancers by dancing with lots of different partners and dancers of all levels.

Ladies
Patience while learning moves in group class, the gentlemen have lots more to think about then the ladies, focus in on your following skills and most importantly the connection you are giving to your partner rather then back leading the pattern for yourself

Gentlemen
When taking a partner on the floor to dance, try warming her up by some nice easy basics first and gradually move up the level of patterns after feeling out whether the partner you are dancing with is ready to follow the more advanced moves. Remember your job is to make her look good and in return you will look good as well.

Beginners
Make sure you have strong basics in any dance you are learning before moving up a level or learning new patterns. It will make the next level a lot more frustrating if you don't know your basics well enough. We all started at the beginning and repeated the first level a few times before moving up and sometimes as intermediate and advanced dancers its a good idea to refresh our memories by taking a basic class again as a reminder of a few things we have forgotten about.