it seems that you are only just starting with this client, so you probably won’t know her all that well yet. You are aware, though, that emotions and her weight have a relation.
If she is okay to weigh once a week, that’s great. Susan’s point of only shooting for 20 lbs. at a time is right on. Nobody can visualize losing 150 lbs.
While the points about body fat are valid, at that amount of weight, any estimate of body fat will be highly inaccurate, and it will be better to go with weight alone. I also would only use one measurement; the waist would be best.
Be prepared for a very rocky road. At that weight, the client is likely to have health and/or mobility issues that will make the start difficult.
I wish you and your new client best of luck.
Bradford has some good points. I usually tell my clients not to worry so much about it and maybe weigh them once every 2 weeks is usually good enough. I like for them to focus more on their overall progress and not been stuck on how much they weigh. The problem is that even if I tell them not to get on the scale any sooner than that, they do it anyway. Body fat is more important than total weight. Also how their clothes feel and look is another way to measure progress and the most important one is how they feel regarding their energy level, mood and overall state of mind.
I have my clients weigh in once a week using an electrical impedance scale that measure both their weight and bodyfat percent. I of course also have them measure their waist, hips, thighs, neck & upper arms every 6 weeks.
Remember, the client realyy wants to lose bodyfat, not just weight, and if being trained properly will understand that even if their weight does not drop for a week or two, their bodyfat percent should.
The most important thing is don’t let them become discouraged by a plateau and go into self-sabotage mode where they just give up!