Let’s get this straight right from the start, sitting down after the fist bump isn’t pulling guard; it’s sitting down. Pulling guard is getting controlling grips on your opponent and pulling them into your guard with control and setting up your attack/sweep, and to be 100% honest with you I’d rather see someone properly pull guard to get a match started than watch two people do nothing standing because neither can score a takedown or a throw.
So; if you do pull guard make sure you have a strong guard game. Pulling guard and then getting passed immediately, or worse yet spending 6 minutes doing nothing but holding guard while your opponent tries to open your guard, is just wrong.
This being said; learn takedowns and throws, practice takedowns and throws, and when you roll in class start standing more often and practice takedown sparring.
In Summary:
Learn Takedowns
Learn Throws
Practice Takedowns
Practice Throws
Start Standing more often
Develop a strong guard game
Develop a complete Jiu Jitsu Skill set……
Train Hard
Train often
Peace