Hey ItsAboutTime,
I weigh every day. I usually only record changes--but if it's been many days with no change, I do record it just so my graph stays accurate-looking.
But once a week is just as good! For a long time I didn't have a scale at home so I could only weigh when I went to the gym.
Lots of folks would say that weighing less often is better--because otherwise the scale can drive you nuts.
Jay