When out on the trails do what Jeffro did and it will get you going again, but the way to get it back to perfect again is to put the bike on a stand and get the front wheel up off the ground, undo all fork bolts in the upper and lower tripple clamps, then spin the forks in the legs to make sure nothing has bound up, being careful of the height adjustment not moving, then tighten up one side top and bottom and as long as you have no bent upper fork legs, then you can be sure the top and bottom are in line, you then tighten up the other side and now it is all square, just be sure not to tighten too much as they wont twist in the clamps but bend, Hope that helps:)