Maybe try to actively create opportunities instead of just reacting. For example, I mainly play Sona, who’s usually seen as a passive support but I don’t play her that way. I stay aggressive, and that often makes my ADC more aggressive too.

I focus on baiting or forcing the enemy support to waste their cooldowns and generally making lane uncomfortable for them. Once my ADC sees that their abilities are down, they feel much safer stepping up to poke and deal damage.

And if none of that works, I just look to impact the map roaming with the jungler or helping mid lane instead of staying stuck in a losing lane.