Because Croatia's Red Cross and their payment processor Paycek.io still don't support DOT and KSM, the process is a bit more manual on their end - the DOT and KSM address displayed on this page are deposit addresses on Binance, where a script is configured to automatically trade the tokens for another token that Paycek.io does support.
The token is then sent to the service for automatic liquidation, as if the donation were paid in one of the other, supported currencies. We realize there is a big trust factor at play here, so we invite you to contact Electrocoin and UBIK, the two organizations behind this effort, before committing to any donation. The contact information is in the footer, along with office addresses and VAT numbers of both entities.
There are two ways to donate. You will either need the Polkadot JS Extension installed and the account you're donating from will need to have some tokens in it, or you can just donate directly to the respective address from any wallet or exchange of your choice unrelated to this website.