Any tips on piercing my own floating helix and which ear to do it on?

I do all my piercings and usually it’s pretty straightforward but for the floating helix that im planning to do tomorrow- I’m not quite sure how to pierce it. Does the needle go directly upwards? I’d appreciate if someone could describe how the best they can! And also let me know which ear I should do it on! (Also don’t mind the rook- I have to take it out soon it seems to be rejecting)