Commercial growers take the colas from the plant and manicure them before drying. They usually dry them on a line, upside-down, which is fine.
However, usually airflow is forced, and temps too high, humidity too low. As soon as the buds are considered dry (usually a few days), it is sold. The reason for this behavior is the fact they are, as I said, commercial growers and in a constant hurry to exchange their buds for cash. Every minute counts and they don't want to 'waste' the space or the time needed for drying and curing. This results in harsh, grassy tasting weed that lacks the full-bodied flavor and smooth stone of properly dried and cured bud. To do it right:
At harvest-time all you have to do is cut the plant as low as possible and hang the whole thing upside down to dry on a line. The room you use to dry should be the about the same size you grew in (if not the same room). The humidity should remain a constant 50-60%. Too high and buds will mold, too low and they dry too fast and taste bad. Temperature should be around 65-68 degrees, wherever possible. Make sure the room is dark, as light degrades THC.
All kinds of processes, like the transport of sugars inside the plant still take place, even when you cut it down. These processes will slowly come to an end while the drying progresses, but are the main factor for the end-taste of your smoke. That is the first reason why you don't want to quick-dry your weed. The second reason is the way that a plant dries. Plants are made up of cells and, as we all know, cells contain mainly water. Exposed to air, the (dying) plant's outer cells will dry out first but the above-mentioned processes will still transfer water from the inner cells to the dryer outer cells, thus causing the plant to dry equally all over. By removing the stalk and cutting off the individual colas, you prevent this natural process by taking away the extra moisture that would be drawn from the stem to the leaves and bud. Got it? Good! Moving on...
Make sure you hang the plants so that they do not touch each other (invites mold). With constant temp and humidity, the plants should be ready for manicuring in 3-4 weeks. At this time trim colas from the main stalk, and trim large and medium fan leaves (save them for making hash), leaving most of the smaller leaves sticking out of the bud in tact. Hang them up again and for a day or two, until 'popcorn' dry. The stems should snap when you bend them, and the bud should be dry, but not brittle. Now for the curing...
Trim all remaining leaf (save for hashmaking) tight to the buds, and trim smaller buds from larger stems. Store them airtight; air at this point degrades THC. Note- ziplock bags are not airtight! You could use buckets with an airtight lid like used for food and sauces and such, but the best containers are those glass jars with the rubber seal and latch. Just put as much bud in it as possible using light pressure. The point is to fill it as much as possible, so not too much air remains in the container. The less air, the better. To be safe, check them the next day to make sure it's still dry (did not 'sweat'). Any excess moisture at this point will invite mold. If it did sweat and is moist (soft) again, lay the bud out on something other than newspaper and put in a dry place to get the last water out.
Repack and place the container in a cool, dark place, like a refrigerator. Note- fridges have high humidity so they must be absolutely airtight.
The longer it sits (up to around a month, maybe longer in the fridge) the better it gets, both in taste and potency. At around the month mark, you can move it to the freezer to almost stop the aging and curing process. Once you've got some buds stored in the freezer, you have a private stash that will last a long time. If you've got the patience to wait, the smoke will be sweet and smooth. The high will be mellow, and longer lasting. If you grew enough to last you a while, then after a few harvests you will be able to have properly cured buds at your disposal, with no downtime waiting for the next batch to cure!
If you're not in a hurry to sell your crop you owe it to your head to wait the extra time and have great tasting, very potent bud! Curing is the only way to make harvested bud more potent, so try it, you won't be disappointed!