I found this on a samsung help forum. It might help
# With the device off, press and hold the “'''Volume Up'''“, “'''Home'''“, and “'''Power'''” buttons.
# Release the buttons when you see the recovery screen and the Samsung logo.
# Use the volume buttons to navigate the menu and select “'''wipe data / factory reset'''“. Press “'''Home'''” to choose the highlighted selection.
# On the next screen, press “'''Volume Up'''” to continue.