Characters not mine.
(Originally written for a woman characters on comment_fic. Prompt was "breast-binding.")
She was lucky in some sense - her breasts had always been small, so she didn't have to rearrange herself or tighten bandages repeatedly in order for them to go unnoticed under the loose clothes soldiers in training wore. Underneath her armor, she probably didn't need to bind them at all, although she'd planned to from the start just to be on the safe side. She knew it would be much more difficult for many other women, to mimic the shape of a man.
In the beginning, especially if she could get Mushu to wake her up, it was a matter of waking up ten or fifteen minutes before anyone else started to stir in the tents around her so she could take the time to get it right, to strike a balance between comfort and concealment that would get her through the day without feeling more self-conscious than she had to be.
Eventually, she got used to the way they felt when the bandages were wrapped right, until it only took her one try and thirty or forty seconds rather than the minutes of adjusting it had first taken her when she had stolen her father's armor and summons. As Ping got more comfortable and confident in the training exercises, Mulan got more comfortable slipping into Ping, until it simply became second nature.
Then, of course, there came the battle in the mountain, and the discovery, and the saving of the Emporer, and Mulan didn't have to hide within Ping any more.
She still bound her breasts, grabbed a staff, and became Ping on occasion, though. Men knew Mulan - and they assumed that she was either perfectly capable of keeping up with them or all hype and therefore easily overtaken. It was Ping who could occupy that middle ground, who they would teach things when she needed to be taught. She didn't want to rely on Shang to teach her everything.
Besides, she could still be Ping, the sheltered boy who had turned into one of the Emperor's better fighters. And if Ping had done all that, then whatever it was she was trying to learn couldn't be all that difficult by comparison.