A harness is very impotant so knowing how to properly put on a harness is very important, below is a step by step instruction on how to put on a harness.
Lay the harness on the ground and put each leg through the waisbelt and the appropriate leg loop. Then pull the waistbelt up to your waist. Then adjust the buckle until it is tightly secured around your waist. Finally you want to tighten each leg loop's buckle. Now you are ready to climb!