I actually find weighing myself daily more helpful but the important thing is you need to remember that the daily numbers don't matter, what you're looking for is the weekly trend.
If you only weigh yourself once a week then that could be the day that your weight for that week has spiked for whatever reason but if you've been doing it daily you can see the actual trend in your weight gain/loss.
If you only weigh yourself once a week then that could be the day that your weight for that week has spiked for whatever reason but if you've been doing it daily you can see the actual trend in your weight gain/loss.