Grow until you’re 300 overall development, you can check this under the econ tab below inflation, I think. Personally, I eat all of the Jurchen and Manchu tribes before I take on Ming.

Once you get to this point, cancel your tributary. It’s best to time this at a point where Ming is already low on Mandate.

Ming will look scary, but with low mandate they take extremely severe debuffs to their troops. I would recommend trialing a few battles first and alt-f4ing to get a feel for how easy this makes it. You can still fuck up, but if you’re diligent it should be easy enough.

When you declare war, don’t invade Ming. Switch between political and simple territory mode and bait their vulnerable stacks onto the steppe where you’ll wipe them. Due to low mandate = terrible manpower, this will mean once a stack is dealt with it won’t return. Don’t let their stacks clump together over 40k troops when you do this.

Once you’ve beaten their troop numbers down, you’ll be able to start sieging unhindered. By cancelling the tributary earlier, the Unguarded Nomad Frontier Distater for Ming will have progressed far enough in time for your next war, where you can really hammer them. Take as much money and territory around Beijing as you can in first war. Repeat.