Step 10: Unfold the last fold you made. Now fold the lower left and right corners inwards as shown, creasing where indicated in blue
Step 11: Fold the left and right edges inwards and crease where indicated in blue
Step 12: Fold the top left and top right corners downwards and inwards until they meet in the centre, creasing where indicated in blue
Step 13: When pressed down, your envelope should now look like this
Step 14: Fold the top point downwards, creasing where indicated in blue
Step 15: Tuck the point inside the envelope to seal it and your handmade origami envelope is finished!