For me, the worst part of the "first" ballroom classes was being very self critical. In high school and college, was always considered a good dancer and even won some sorority and fraternity dance contests. However, dancing "free style" and dancing ballroom are two different animals. I didn't pick up on things as fast as I wanted to...it took some work. And like most other beginners, I took the beginners class several times...each time building upon that all important BASIC.
The more experienced dancers in our group always insist the most important thing is the BASIC. If you really LEARN the basic, understand how to FOLLOW a lead, and keep the timing...baby you are home free. Get that basic so you can do it in your sleep, waiting in checkout and Walmart, and showering in the morning! If you take a misstep, well apologize the first time...but just keep going. You'll get it. As others have mentioned, most of the members of your class are just as nervous as you are about getting it right. Take a deep breath...and Just do it!
Also, when I first started with group lessons, I really hated it when the teach would make me partner with him in front of everybody. AHHHH! However, once I got over it, I really take pleasure in dancing with the teach. I try to forget about everybody watching and just enjoy the dance. If you do screw up, well everybody really wants you to do well...so they'll cheer you on anyway. Who knows, next week they may be the ones with two left feet HA!
And one last thing, about us plus size girls. I take pride in being LIGHT on my feet. Visualize Fred and Ginger floating across the dance floor....and you are halfway to the clouds and on your way to the starlight ballroom. Smile at your partner and have fun!
Happy hoofing
Joyc