How do i start tumblr and twitter?

[Carrie]

Instead of asking two separate questions, I'm just gonna knock both of them out right now. Okay- I got got a tumblr and twitter today (I know, I'm late.) and I'm not sure what I'm supposed to do, especially on the tumblr. Like, do I post stuff about myself and junk, or about my favorite band or something (since thats all I really see tumblr used for?) Do I do the same with my twitter, and I don't know what to "tweet" about? "I'm eating a sandwich. #pbandj" -stuff like that? That seems kind of silly to me.
Before you criticize me for getting these things just because everyone else has them, yeah i already know. I'm on spring break and I'm bored out of my mind so I thought it would give me somthing to do.

(P.S. Also, whats Instagram?)