answer:You have to first start with what your income is…per week or per month. That is the given. Then you deduct your obligate expenses…rent/mortgage, food, gas, taxes, utilities, health insurance, telephone, telecommunications, car payments (perhaps some savings). Whatever is left is your discretionary income. That means you can spend it on what you want. Most of us can’t buy everything we think we cravet, need or can’t live without. One pair of Jimmy Choo’s, or six dinners at a restaurant? You choose.