erm, maybe go on www.tftunedshox.co.uk and find out what spring you need (using the spring calc on the site) then set the rebound for what trpe of riding u do, slower=not as absorbent, but u dont get bucked off the bike during a big hit, faster=more responsive, but a big hit may throw u off the bike. then compression, (im not 2 good with this part of the shock ) judging by the looks of the age of the shock, im jot sure wether the compression is high or low speed, so try out different settings while riding, more compression normaly meant the shock will ramp up more/be harder during the compression of the travel, and vice versa.all of these settings are also down 2 what kind of eiding u do- if ur a DH racer, u may want the shock 2 be softer, but faster, or if u'r a jumper, then maybe harder(spring or compression)and slower rebound. its all really personal preference, so try it, and see what feels best EDIT- make sure u have enough air in the chamber, if u have 2 little, the shock will damage, phone tim flooks, &they can tell u how much the shock needs 4 ur weight&shock etc.
in the manual it does tell you exactly how to set sag etc, its somethin like eye to eye distance - distance of shok wen ur sitting on it normally and the remainder is the recommended sag, something along those lines, hope that helps man
ok, theres probably 3 things you can adjust on there, the compression damping, rebound damping and preload.
the rebound is going to be the one on the right (the red knob) it should say on it which way is faster and slower rebound. (off the top of my head i cant remember which way is which, but i think that clockwise is slower rebound).
to set this up, put it roughly in the middle of its adjustment and ride some trails, bumpy ones are better, then adjust the rebound slower/faster until you get the rebound set how you want. (remember to balance it to not be too fast if you're doing big jumps as you may get bucked off if it's set as too fast.
the compression is how easily the shock is pushed in. again, it depends on the type of trails you ride. if there are no jumps, only bumps then low compression damping would be good, unless there is a lot of pedal bob (search the forum if you don't know what i mean).
The preload is the amount of pressure put on the spring before you sit on the bike. it is the ring which winds down on to one end of the spring. this can change the amount of sag (again, search if you dont know what i mean) by around 2-3%. not too important for you if you have to ask how to set suspension up. only turn this twice clockwise from the point at which it engages the spring, or it can be damaged (well, that's what the fox website says).
trial and error is the way forwards with set-up. keep fiddling and you'll eventually find out exatly what is right. if need be, write down how the adjustment is set at different points during the trial and error stage, and how you like the way it is set. then you can run the perfect set-up.
any questions? you know where to go. hope that helped.