Log in to your OGame account and enter the game. Click on the "Shop" button from the menu on the right.
Click on the "Purchase Dark Matter" button.
Choose the pack of Dark Matter which corresponds to the amount from the reward you've selected on Gamehag and select paysafecard as the payment method.
After an other window appears, enter the code you've received from us. After reading the Terms of paysafecard, click on the "Pay" button.