Initially, learning from books and videos -- I can give you recs if you want? That helped build up a movement vocabulary. Watching lots of videos of great climbers. Then I think outdoor climbing has helped with my footwork, because the footholds are so much worse than they can be indoors.
But still, lots of drills! Things I read up on and then try to practice.
Sorry for the belated reply
But still, lots of drills! Things I read up on and then try to practice.