I gave up and wear my hair down all the time. It looks messier but I prefer the feel of it down - I've learned to let the wind do what it's gonna do and fix it when I get inside.
Claw clip on my bag strap or hair tie on my wrist in case I want to keep my hair out of food or I need to look down AND have both hands free. It doesn't hold forever but long enough to accomplish one-off tasks.
I get that it doesn't work for non-casual environs or extended physical activity; sorry!
Just get used to looking messy, having hair in your mouth, and having large areas of vision obscured (oops sorry I didn't see you there!

). On the upside, it gives you something to hide behind if you're having a moment.
Or start practicing buns and braids, tons of vids on YouTube!
Skip the flat-ion if at all possible (they're super bad for hair, mostly). Good luck, and enjoy your hair!