what kind of feeling/or look should you project when you dance a waltz ?

The usual projection is dreamy and blissful, but if you just paste a sweet smile on your face it won't work well. I believe that you need to discover for youself what waltz means to you, and project that. Try this exercise: put on a few waltzes that you really like, pieces of music that really make you think and feel things. Then start dancing around. Don't think about your steps or technique, just focus on the music and how your body feels while dancing to it. Notice what emotions come up. Maybe a certain step will make you laugh. Maybe a phrase of music will make you feel sad. Let these feelings show as you dance. It takes some practice to get comfortable/used to/good at doing this. But the payoff is that you then start projecting what YOU feel in the waltz, and the expression is genuine and natural.

Laura