It's very dependent on the humidity where you dry them. Sometimes i dry them in a cold basement where it takes at least a couple of weeks. I hang them with the fan leaves on, and usually when fan leaves are completely crisp it's time to go to jars. Just remember to open jars every day for about 10-15 minutes. If you see/feel a lot of moist in the jar after first day in it - take out the but to dry on a paper or something for 1/2 or so - then back in the jar again.
If you are much in doubt about how - make sure you dry them too much and work with that - next time put it in the jar when containing a little more moisture - after a couple of times you'll get it just right.