Try to become more ambidextrous in all aspects <brushing your teeth, washing your hair, reaching for things, drinking, eating, etc. with your left hand>. I've learned that not only does this seem to strengthen the hand, but it helps you to instinctively use it without thinking about it <learning to think left handed, so to speak, so it doesn't seem so awkward to play left-handed and left handed drumming comes more naturally / fluidly>. As I've said before, this is about learning to mentally approach drumming from the other side.
Also, I'd say play your hat left handed as much as possible, whether you play open or move your hat to the right like a leftie.
Also, do lots of rudiments with a metronome out of books such as
Stick Control, etc.
Also, lead more with your hand more during fills <start the fill on the toms with left handed sticking> and crash with your left hand <a.k.a. "equal opportunity crashing", as Mr. A calls it

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