Make your spending habits consistent. Large expenses should be pro-rated over a period of time.
Refrain from using your credit to subsidize your income.
Know your priorites. Allot enough income for the essentials (shelter, utilities, food, medical, savings).
Look for ways of saving money on expenses and eliminating non-essential expenses (entertainment, cable, cigarettes, shopping).
Make the budget a family project. Everyone must be involved in order for it to work.