Humidity should be about 50% in the room, but a range of 45-60% is still pretty safe. A major factor is keeping good air circulation around the buds. Do not overcrowd them, I like to ensure branches are never touching one another while they hang. A fan blowing around the room but not directly on the buds is also helpful. Lights off is best, but an absolute must.
I tend to trim my branches before I hang dry them, but others will insist you leave all sugar leaves on and remove only the large fan leaves. Either is fine, people are successful with both methods. Hang the branches until the stems snap rather than bend and the buds are just about crispy to the touch.
What comes after this initial drying is very important and pretty easy to screw up; that is the final cure. I like to go from drying the branches to getting the buds directly into a glass jar. After the buds have been in the jar for 24 hours they will feel rather moist again, this is the moisture from the interior coming out. At this point I begin to leave the jar open for an hour or two twice a day. This process is continued for approximately 4 weeks, at which point the buds should be dry to the touch and easy to break apart, but not falling apart.
This is just the process I have had success with. I am sure others have their own methods as well.
