As Pat said.
Though, I only can get to dry right if they
not too young.
They have to be around 2-3 years old to dry correctly.
(If younger, they will shrivel up like prune....)
When drying, it good to keep them inside or away from element maybe 2 weeks.
After that, they should loose most of their moisture and from there, bath them in the sun from time to time.
This further dries them and bleaches the skin so it may become more yellow.
I also think it hardens it more. I once did not sun bleach a bamboo and it felt rather weak than bleach one.