If you have the scale at home, you can weigh yourself anytime. If you want to keep a good diet, of course it is better for you to weigh yourself before and after dinner. You may find the way that suits you.
When I was young I would weigh myself too much. A few times a day. The batteries in my scale die in the moisture from our bathroom so I stopped using it. The doctor weighs me every month I go for medicine refills.