charge battery fully before hard reset (and backup)
press and hold volume up+home button (or volume up+down)
keep pressing these 2 buttons+press power button for 2-3 seconds
Releas only power button, but keep pressing up+home buttons (or vol up+down)
with volume down select wipe data/factory reset (3rd) press power (or home)
with volume down button select (yes-- delete all user data) click home button
hard reset done.