Whether your garden is big or small, outdoors or indoors, training your cannabis plants will greatly increase the quality and yield of your grow. Techniques are divided into two categories: LST (low stress training) and HST (high stress training). LST does not involve directly damaging your plant, while HST involves breaking or removing parts of the plant.
The goal of these training techniques is to alter the chemical balances in the plants. If left to grow naturally, cannabis will choose to produce one main cola (the topmost bud) that will reach as high as it can, but this is not optimal for yield and quality. In an indoor garden, you can only bring the light as close as the top cola allows. Buds found lower down on the plant receive less light. Training your plants properly, however, will allow for more even canopies.