If you're a melee support, use the relic charges on the second wave instead of the first wave
I recently learned this from a friend. Instead of using the charges on the first wave to get the recharge cooldown rolling, use it on the second wave to get level 2 before your enemies. This way you also don't use up the proc and waste the heals.
This is especially useful for champions who go all in at level 2 (which is a lot of relic users).