I have done that but how do I change the coodinates?
After you hit mark, you should be on the edit screen. Use your joystick to scroll up to the coordinates. press down the joystick, now you can edit the latitude. Then press doen on the joystick again. edit your longitude. press down on the joystick. now scroll down, give your waypoint a name, scroll down to save. press down the joystick, and you're done.
Ok I have done this now how do I actually edit the data?