I like to weigh daily. I've accepted the fact that there will be day to day fluctuations. If I see a gain, I say "hey, its a fluctuation and normal and I'll see a loss in a couple of days". If I see a loss, I say "BOOOOYA!". So, its a win-win situation
I'd try daily weighing for 1 week and see how it goes. If seeing a gain totally depresses you and ruins your day, you should go back to weekly weighing. I even know some people who think weekly weighing is too much and just weigh in once a month.
As is most things dealing with weight loss, there is no single right answer.