The standard that works for most kinds is to pinch/partially-pluck the long new shoots as soon as the needles begin to stand up (circa Mayo - may produce a second flush). Within a month or so, buds will have started forming before the new growth has hardened.
When you prune, always keep a bud on a branch/shoot; else you will likely have a dead branch(let). For me it has been best to wait until around August to cut back to a bud - I don't get as much back budding when I do this earlier in the season. Branches are largely independent, so you can experiment on each branch instead of the entire tree one season at a time, at a time if you want.
Like most conifers, they tend to be very apically dominant, so you will always be heavily pruning the top to get/keep low growth.