I mostly play enchanter supps at the moment.
It's important to create as much of an oppressive lane as possible to help your adc farm/make plays and most importantly stay alive.
Harrassing from the bushes is key as it forces the opposing lane to use wards and potentially limit their own vision from river to help your jungler gank more easily.
It's also important to recognise when your ADC is not farming well and look for other opportunities on the map to help make plays if this is the case.
I mostly play in front of the adc and only take a more passive stance when we need to recall or the ADC is over-staying, this is to signal (as well as pings) to your lane buddy that it's time to go.
The most important thing with supports is to remember that it's your job to dictate to the enemy that they cannot get away with anything without being punished.