hang upside down as much as you can. It'll decompress your spine and allow more growth to occur.
I've seen a study where it added 15% in 2 years! I know that's a long time but think about it: in 2 years you'd be 5' 10''!
You have to hang upside down for at least an hour EVERY DAY for it to work, otherwise your spine re-compresses.
Wearing a heavy hat increased growth in some individuals by 2%, but it didn't work for everyone. A trilby filled with gravel is what the researchers used. It might be worth a try.