Clear the expensive debt first
With several debts, put every spare euro against the one with the highest interest rate — usually a credit card or an overdraft — and pay the minimum on the rest. That costs the least in total interest.
The other approach also works: clear the smallest balance first for the momentum. It costs slightly more, but for many people finishing something is what keeps them going.
Keep a small buffer while you do it
Throwing every euro at the debt feels right until the car breaks and it all goes back on the card. A modest emergency fund alongside the repayments is what stops that loop.