~~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.