Train restraint before power expands your options.

Restraint is invisible when your options are limited, because there is nothing much to restrain. It only shows up once you could actually do the thing, which is also when it is hardest to develop from scratch. Practising it early means the habit is in place before the options expand.

Find somewhere you currently could push and choose not to. Not out of fear, out of judgement. Learning where your own stopping point is now saves you from discovering you have none later.