[c-152]

I have to admit that as much as I am confident about most of the mechanicals of a motorcycle, I am completely lost when is comes to springs. I can change for seals and know how to set everything back to factory, but to tune it, I am lost. I am currently in the process of rebuilding my 99 gasgas ec250 and had planned on (based on a few suggestions and nice offer for purchase) switch my conventional zokes for newer gear, however due to cost overruns on other parts, I was not able to put the money into it at this time. Because of this, I have decided that, at the very least, I should get my suspension that I have working properly. I do know enough to know that that requires a lot of research and careful trial and error. I was hoping to find a few quick points from guys on hear familiar with my bike for correct setup. To this end, I have the following questions.

1. I am a 210lb (full gear) C trail rider from southeastern Ohio. I also race harescrambles and would like to keep the bike set up for racing (being that I am a C rider that probably means trail setup for you A guys). What would be the first big setup concern?

2. Does anyone have any other good tutorials (video preferably, I am visual) to help me learn about this stuff?

3. My rear OHLINS shock is stamped 596-12/58 L481 - Part number or does it mean something.

Thanks for any help. I am not expecting this to be spoon fed to me as I understand that a lot of my own research and time needs to be invested but a few starting pointers would really help me direct my search.