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.
Your next task is to identify all your expense areas whether they're irregular or not. Set up two columns for each pay period (as shown below); IMAGE NOT AVAILABLE HERE The first column called "Bdgt" is the portion of your income that each expense area will be assigned. The total of this column should never exceed the income you receive for that period. The second column "Used" shows a negative amount and is a record of what has been spent from that period. The beauty of this system is that it will always give you a running balance.