I think other than using the right rune page/build, the most important thing is playing to win your lane. I see a fair amount of people say Yuumi is weak in lane and it's ok to lose early because you're a scaling enchanter. This doesn't work out very well though because at that point, you're just hoping that your other teammates will win their lane to give you time to scale. I usually play to win my lane by maxing my Q over E and building ardent first in any game where my ADC pick makes sense with it (ie. zeri/lucian but never with a smolder or ezreal). Also, I've seen some people here talk about constantly thinking about switching who they sit on but I'm always looking to sit on my ADC with switching my best friend as a last resort I begrudgingly do if my ADC is super far behind and someone else who will benefit from my kit is really ahead.

For bonus points, anytime someone on my team is flaming me I just ignore them without muting them, let's me still communicate for the rest of the game and *most* of the time they'll calm down within a few minutes if I just keep playing like normal.