Break your finger /j

On a serious note, I dont really know any good inkbrush tips, but some good guides are this one by paxCaster, and this one by Phonochirp. Phonochirp is a bit slow tho, so if you want to watch that one I recommend setting it to 1.25x speed. You can also go to sendou.ink and look at builds and VODs for inkbrush. Hope this helps :)

Put all your gear to run speed up to move faster

For actual advice, check out some of the gear builds people made on sendou.ink for the brush. It looks like quick respawn is pretty popular right now, but you should always experiment too. DUDE has a Tearin’ it up video on the inkbrush (splatoon 2 but still relavent) which you can watch for strategy and ideas. I heard rolling is also super important to psych out people with inkbrush. You have to be super mobile to not die, and squid roll really helps with that.

I started using inkbrush in Splatoon 3 (originally an Octobrush main) and what I find helpful is using the roll mode (holding down the shoot button) to psyche out people shooting at you. Your movement speed in roll mode is pretty hard to contest.

Running sub saver (if you’re using the vanilla brush) also helps a lot too so you can throw bombs without using all of your ink. That way, you could roll a bomb on the ground, move in with your brush, and pressure them on both ends.