Ok, start with marking one of the blades with tape at the end (tracking tape or any other bright colored tape will work) set the heli away from you, run the engine until it looks like it's ready to lift off, now you should be able to see which blade is lower or higher, now let's say the blade with the with the tape on it was too low, shut down the heli, set it in front of you, and turn the rotor head so that the marked blade (which was lower) is on your left side, now the link right in front of you is the one you want to adjust, to make the blade track higher turn the link out (make it longer) you could also make the opposite one shorter to bring the other blade down. I hope this helps
Good luck and be safe not to hurt yourself, First time I've learned how hard my LMH bites was when I was trying to track the blades, but that's whole another story