Found a lot solutions on this site when I was searching PSP stand.
I am going to introduce the simplest and very stable one here.
Step 1: What You Need
one or two floss picks
Step 2: Cut the Tail of the Floss Pick
cut the tail of the floss pick by scissors
Step 3: Put the Pick Inside PSP
Put the pick inside the strap hole of the PSP whenever you need it stand.
Step 4: Detailed Picture
The PSP will stand stably even if you push it.
Step 5: Enjoy Your Film
enjoy your video film or music display now!