At the top of any wedding budget worksheet you have the 6 most important categories: the wedding gown, bride's accessories, hair & make_up, groom's attire, groom's accessories and the wedding bands. These are the things that should always be budgeted first. After that, you have the following categories: the ceremony rental, the reception rental and equipment, celebrant's fees and flowers. Once you have budgeted money for these categories of expenses, you've got all the necessary things to get married. But of course, you have to accommodate the guests better than that.
First of all you need to know how much money you earn, for some people this is easy you look at your Wθ form and there it is, but for seasonal workers, small business people, it gets a little more complicated than that. If you receive income from a lot of different sources for a realistic value of what you actually earn itemize them, put them down on paper. Include all income, now is not the time to be hide money from the IRS you are just fooling yourself, you need to have factual figures here of your true income otherwise you will actually think you're in good financial shape because you know you got this extra income somewhere, but that's not always true.