Load with one round. Shoot. Repeat twice.
Load magazine with three rounds. Try to get a two shot burst. reload and repeat as often as needed to master that trigger.
Load magazine with four rounds and try to get a three shot burst. Repeat.
When you can get a single, double and a triple burst on demand, then you can try sustained fire. When those bullets climb too much, release that trigger.
Vigilantibus et non dormientibus jura subveniunt. Molon Labe!