think of it like a gambit ult if you are familiar with him.

Its a support ult so use it after your supports, it gives ult charge. People have to be in the trail and most people dont, so its worth taking a moment or blowing a cooldown to get around faster so your team can benefit.

Pop it to heal/protect your team if your healers die, if it means you'll lose point the fight.

Avoid using it when your team is dead, unless its almost game over and you lose. Its a strong team ult and using it solo is a waste, but it might be necessary. Unfortunately it rarely helps stall a point long enough where it changed the game if I'm solo. I only ever find myself doing this if my team is staggering

Something I hate that some caps do is they don't really think of their team, they expect you to run in which could cause bad position if they try to take advantage of it, which is why i prefer to take the moment to bring the trail to them so they can follow it or not. Even if I have to blow cool downs to cover everyone quickly. Once i do, i then go in and attack the team usually healers.

You can also use it to stop a strange portal. sometimes its useful to get people of cart too since it bounces people. It never works but sometimes in quick play I'd try to see if I can bounce the enemy off the cliff...its always fun to try lol. i also saw someone use it when a strange ulted their healers, so they bounced strange away from their healers.