So the suspension on my bike atleast the rear suspension is totally worn out, when i hit medium sized jumps it bottoms out everytime and i only weigh around 160.  What can i do myself to stiffen up the suspension until i can afford to send it in to be rebuilt, or should i try to rebuild it myself?

Basically is it possible and what will it cost me (roughly) to have my suspension feel like that of a new bike?

I had a 91 rm250 and had the same issues. I did not want to spend $ so I just tightened the shit out of the back shock and eventually had to shell out for new fork seals. The only problem I ever had with that bike was the damn suspension.

I just got a hammer and flathead and tightened until I could not get it to turn anymore. Probably not the best way but seemed to help