The folding note is a very visual trick. The method is quite automatic so it does not need too much practice. This has been shown on TV shows and always gets a good reaction.
This trick does need a gimmick so you will not be able to hand out the same note for inspection but with a small sleight you could pass a standard note out. Using a similar technique before the trick you could adapt it to borrow and note. Make a joke by putting it in your pocket and pretend to walk away and then perform the trick with your gimmicked note.
The gimmick is very easy to make and will cost no more than a few dollars to produce. In fact you may have most of the required materials around the house.
This trick is suitable for all levels.