I weigh myself in the morning (after using the bathroom), in my pajamas and before I eat breakfast
It's been my experience that my weight can vary from 2-3 lbs during the course of the same day, it all depends on what I eat, how much water I drink and what kind of exercise I do. As long as you weigh yourself on the
same scale at the
same time of the day, your weight loss progress should be pretty accurate.