Ok, this is hard for me to explain because i dont know the proper terms for everything but i will try...so plz bare with me...I will start with the sides that you stand on to take a breather (at least i do)...follow them back to where they end...there should be a hole in each one where a wrench will fit, its prolly an allen key that u have to use (it is for ours), insert the right size tool in the hole and with ur speed set on approx 3.5 little by little turn the key while the belt makes some revolutions, you will know which way to turn it when you watch ur belt move, then basically it is a trial and error thing. when ur belt is back to correct position just stop...ur done!!