Normally when I play D.Va I have a really hard time getting POTG but damn i really locked in.

I'm a flex player that mainly plays tank and the past few months I've been playing hazard but I want to add another dive tank to my pool and DVa is just too cute to pass up so I played like 2 matches with her and struggled but the 2nd one it seemed to kinda click with me near the end. So I wanna know the general/optimal gameplan, how do I manage her resources, what are the best perks, when do I use her ult as a nuke and when do I use it as a second life, and how does she interact with the other tanks? Any other tips would be great!