I know it won't get as flat as a chest binder would, but does anyone have any ideas?

I don't really know, but be sure not to bind your chest with the nips facing down, becuase that causes issues with your chest sometimes. Instead, bind them like you are pressing your breasts back into your chest, it's much safer that way.

Thank you for the advice, I'll be sure to remember that

I don't know that answer but I love the dear evan hansen fanart

Thanks!