I learned a good pirouette practice combo over the summer
This is to train better preps and more controlled finishes. Each step takes one count:
2.) Rond de jambe to back
3.) Lower the heel in 4th position, but keep the back knee straight, so you're in a small (and rather uncomfortable, I dare say) lunge. This is to train yourself to keep your weight over your front foot.
4.) Bend the back knee. Keep your weight forward.
5.) Releve to retire (no turn, just releve)
6.) Plie the standing leg, but stay in retire. Keeping that foot up in your pirouette longer gives the illusion of a more sustained turn.
7.) Lower the working leg to 4th position
&-8.) Tendu the back leg, close to 5th
(credit to Josh Trader from Ballet West)