credit card debt

Pay your bill in full when you get it if you can.

Live within your means. If you are considering buying a higher cost item, ask yourself if you could save up the price in 6 months. If the answer is "no", you can't afford it.

There is only sure one way to avoid debt: don't borrow money. Since using a credit card involves being in debt (that's what "credit" means), we suppose you mean excessive or unmanageable debt. You can avoid that by not using more credit than you can comfortably service.