If you can't afford it, don't buy it. Try not to use credit or make a loan, if you can help it. Always remember to pay all your bills first before you go shopping.
Stone Cold is right, always save for the rainy days (just like the ants) There's always something unexpected coming up every month. Like birthdays, wedding, or you might get sick, or family emergency and you might have to send some money or worst yet, you might have to go home. While you are still young and have a good job, save and plan for the future so someday you can retire in luxury.