Gathering in your first good harvest is for many growers one of the most wonderful and exciting events of their lives. Finally the time has arrived... the product of your creativity, hard work and perseverance is ready to come to fruition. The harvest is ripe when the "hairs" of the lowest buds are for the largest part brown (or red) and once the "hairs" of the uppermost buds are partly brown. What you will see then is that the empty seed boxes are completely formed. If you wish you can harvest a little earlier or a little later. If you choose to harvest earlier then the plant will have made THC in particular. This THC makes you more stoned. If you harvest relatively late then the THC will have partly transformed into the psycho-active CBD and CBN. These substances mostly make you "stupid". The choice is up to you whether you want a more "stoned" or a more "stupid" high.
Of course, it is the case that harvesting relatively late is the best option commercially. The buds are then at their heaviest. When growing for yourself then at least you can try harvesting a bit early. What you can also do is harvest the riper buds while leaving for later the less ripe ones. But take care – you can leave the plants too long before harvesting, and then the potency will rapidly fall, under the influence of the light and wind. The crystals that are normally see through and colourless will become brown (use a magnifying glass). It used to be common everywhere to trim whole plants (to remove all their leaves) and hang these whole plants upside down on a line and then let them dry slowly in a dark, ventilated room. This process is called wet trimming. Once the plants are largely dry then so-called dry trimming can be used. The buds are then cut off the branches and left to dry out further on newspaper.