During my week in CO last week, we leaned after start and during the run up, both of which were checklist items.
MidlifeFlyer's technique is exactly what we used for the week - three twists of the mixture knob - but on my checkride my examiner showed me one additional trick.
After setting the mixture as described above, he would fine-tune by advancing to [nearly] full throttle. If there was a miss or cough prior to developing power, he would throttle back to run-up power, lean the mixture, rinse, and repeat until the engine smoothly advanced with the throttle.