My best advice...
1. relax and listen to the instructor.
2. work every session on your shrimping and guard pass.
3. Don't worry about getting tapped, if you have an ego about being tapped it will hold you back
4. Go for stuff. Even if you mess it up and end up underneath you will still have tried to get a sub, and besides now you can work on your bottom game
I find a lot of beginners spend the first 6 months trying desperately to keep as tight as possible and not going for anything because they don't want to get tapped. If you throw caution to the wind and just go for stuff (obviously in a technical way) you will progress much faster.
Luck,