Good luck and good growth my friend
Handling begins as soon as the plants have between 3 and 6 nodes or a pair of leaves.
And during this first stage of growth, the trunk is still flexible and foldable without the risk of it breaking, even if as the plant develops it will be more and more difficult to fold it.
You can continue to guide the growth of the branches during the whole cultivation, even during the flowering, which for this stage represents a big advantage vis-a-vis the size, which is not at all recommended once the formation of the heads begins, this will stress the plant, which will delay the harvest.