I practice alone, no mirrors, no camera, nothing.
When I feel like I wanna perform, I perform.
I don't choose tricks with palming, or pass anyway.
So nothing much to be flashed.
Practicing with mirror or camera is different form real human point of view.
The best way is to practice with magician friends.
But yes, they can't be with you all the time, and I believe that mostly you won't spend time with friends practicing magic.
Performing is better, in other words, every of your performances are practicing.