First off, here's a link
to the user manual for this remote, in case you need it.
To do a regular user reset, use the 980 command. To do a full factory reset, use the 981 command.
You enter it like this...
1) Press and hold the SETUP button (ie, the "P" button in the top left corner), 2 flashes
2) Type 981, 4 flashes