Spray the nodal areas, and branches and tops. It is not necessary to spray the entire plant and all of the leaves. A fine mist will do but be sure to get an adequate coating.
This guy documented how he went about using STS with autoflowers.For autoflower cultivars, spray as soon as the first signs of reproductive growth are visible. Spray the plant every other day for a total of 4 sprays. It’s very important not to expose the plants to STS after the flowers start to form.
They advise to spray every second day because their STS is diluted. Undiluted STS works when applied as a single spray.I initially used another pre mix brand from USA, who also instructed to spray their formula for one single application. So the number of spray applications correlates to the strength of formula used.This seller of STS says in their instructions:
This guy documented how he went about using STS with autoflowers.
If you google "cannabis STS autoflower". Theres a bunch of other info, seems like ILGM have a few how-to's.