Step 1: Width and Corner Folding
To begin, fold your paper in half along its width. Once it is folded in half along its width, pull the corner folds down.
( yeah I copied these sentences from OrigamiAirEnforcer, and pictures too. :D )
Pull the tip of the nose back so that this tip lies 1 inch in front of the trailing edge. Then pull the corners in once again as shown.
Step 3: In the Name of the CoG !
Then open your folds, and tape your paperclip to the front of the plane. Be carefull - tape it in the center and as you can see from the pictures, the paperclip's "sharp" edge should be facing forward. Then fold your airplane again. And tape it as shown.
Flip your paper airplane. As you can see in the first photo, I drew a blue line on the wing. This is where you going to fold it. Fold 2 fins for the airplane on both wings. Once you finished folding the fins, fold the fins in half. Pull the top of the fin to the bottom and fold. I know my english is not so good but you can easily understand what I mean from the photos.