The best, simplest way would be to follow the drying sticky'ed thread with a hygrometer.
Ideally you are looking for Fairly dry, but you don't want the stems to snap like they are brittle. But they should just sort of snap. If you squish a bud and it permanently becomes a pancake it's probably too wet to cure.
If you are not using a hygrometer.. I'd suggest you keep a very close eye on the buds. I would also consider a middle step like paper bags, or paper bag alternative. (This may have an effect on smell quality?)