How can I change the display order in my PSP?

When i copy my music to my PSP they will appear in a pacific order, now is there any way to change that order (move songs up or down)?How can I change the display order in my PSP?
You can't move them on your psp but what you can do is before the song title put 01 xxx 02 xxx 03 xxx and etc. You can do that if you want to set your song from good to bad in order.