I trim off anything without trichomes, leaving me with close trim that wraps around the buds as it dries...protecting it from light and regulating the moisture loss, keeping in the aromas, allowing it to happen slower thus increasing the taste and reducing harshness.
Then I snip the buds off the stalk when the stem snaps but there is still enough moisture to keep the stem somewhat intact. Some people will disagree and say to wait until it snaps cleanly...this is too dry for me to start a proper curing process. It also depends on your bud density, I tend to grow sativas so they dry quicker.
It is a pain in the ass to do but...if you are able to trim and dry the whole plant without breaking it down into smaller pieces, do it. This seems to help the finished product dry a bit more evenly and slowly. Its also more difficult since you cant work with smaller sections....
when dried adequately....then trim the remaining leaf and use it to make oil or your preferred concentrate.
