When should I use Cloak and Dagger’s ult?

Im in gold right now, and as I play comp, I realize that i might be holding my ult too long. I get a good amount of heals each game but I feel like i could do so much more if i know when/what situations to use my ult. I know to use it to take space or help in team fights, but when?

like if it’s 3v3 should i wait to pop it until people are back?

if the team is all alive but low ish and could potentially be healed?

if the team is low but the enemies are pretty much one?

to negate any ult?

those are just a few situations, any insight would be appreciated and if you think of any more. Thanks!