As a fellow ADC main my over all adivce would be to play stronger adc's in the meta. But, on xayah specifically you generally need to have an objective in mind based off your powerspike. Lvl1 your only goal is to get lvl2 by clearing and dpsing wave as much as possible. Once you are lvl 2 you can harras and look for trades.
Xayah combo's are usually leading with a W impowered autoattack into Q then E. A tip is once you've pressed q you can e and send feathers out at the same time as you pull them back and they will return to you and bind a Target even if they are late. This is benifitial because it doesn't let an opponent have time to react they think they won't get binded but the q you just here out returns late and binds them. People become warey of feathers on the ground so don't give them a chance to position away from them.
Always pull feathers for 3 hit bind don't get greedy for more damage because the vast majority of the time they will position or flash away before you get damage off where if you hit root instead you can AA dos more potentially killing them.