I've actually read recently ( can't remember where but I'll find it) that you should only weight yourself once a month, on the same day, around the same time. Apparently, weighing yourself everyday discourages more people then it incourages. It is also a good idea to take your measurements (arm chest/bust waist, hips thigh, calf ) once a month as well. This way you can see progress in more then just pounds.

I would suggest weighing yourself every day for a couple reasons:

-it makes you aware of a range of weights that is normal for you
-it keeps you focused, giving you one source of information for your progression towards your goals

But, don't let it get you down. I've weight myself in the morning and at night on the same day and had a 5 pound difference depending on the time of month, if I've just eaten or had something to drink, etc. Obviously, I didn't gain 5 pounds in a day, it was just a normal flux. if your weight consistently climbs, however, weighing yourself regularly will remind you that you might need to reevaluate your exercise routine or your food intake.

Now that I've said all that, don't base your goals on a 'perfect weight,' rather, concentrate on body fat %. Get tested at a local University or fitness center, and go back every 2-3 months to get tested again. This is one of the best measures of health and fitness that you can have. Don't sell yourself short by using weight as your goal.

I have always read that you should only weigh yourself once a week due to the standard 2-3 pound fluxuation based on the time of day, water/food intake, work out schedule. I have also read that by weighing yourself in the morning provides a more accurate reading as you have most likely not consumed food or drink within the past few hours and also because you have not preformed any type of work out. I know you can always find supporting evidence to believe what you like, but this theory makes sense to me because I tend to get discouraged when weighing myself every day. In addition, weight loss is generally measured in weeks, shouldn't weighing yourself be on the same standard?

I actually only weigh myself when I go to the doctor and use one of those really accurate scales with the weights. You should see the machinations I go through to try and get the lowest number possible ... taking off my shoes, removing any "heavy" clothing.

It's always a dispiriting moment for me because the result is never what I would like it to be.

I weight myself everyday, too. It helps me to stay focused and I get a good sense for my weight-range.