These are three of my favs from giftsbeauty.com
Check out Tadashimori's video's on Youtube. (I think he runs Gifts Beauty)
His origamis are AWESOME.
The letter folding is very simple :]
I'll explain each in 3 steps
Step 1: Style #1
This one doesn't take long, and is really easy to open. I tried making a cp for it (the graph below), but it didn't work out very well. I think I messed up some places.
But if it helps, I'd like to say that the red lines represent valley folds, and the green ones are mountain folds.