First you need to add your character to your profile.
Go to
http://noscrubs.net/community/profile/edit and then click the "Iris Online" section in the left sidebar, enter your character name exactly as it is ingame.
You should also select a birthdate in the "About Me" section otherwise you won't be able to save your profile.
Click the Save button to save your profile.
To donate, go to
http://noscrubs.net/iris/topup/card-and-wallet-payments and choose your payment method (Paypal, Paysafecard, Mobile etc.) and the amount you want to donate and then follow the instructions.
If the donation is successful you will receive the moolah directly in your giftbox. It usually arrives immediately but can sometimes take longer if it's your first time or if you make multiple small donations.
Let me know if you have any questions.