1) Navigate to your Gratzio wallet. If you see following warning message please send 3 XLM to your Gratzio wallet account to activate it. Gratzio is based on Stellar network and Stellar accounts do not work with zero XLM balance. You can find more information here. Skip this step if your balance is 3 XLM or more.
2) When you Gratzio wallet account balance is positive you have to create a trustline to Gratz token (you can read more about Stellar trustlines here). To create a trustline just click “Create trustline” button (see on the screenshot below) and provide your wallet password if required.
IMPORTANT: If you created the trustline before the September 21st, you have to remove it and create again. Otherwise, you will not be able to receive tokens. Just click “Remove trustline” button and provide your wallet password if required. After this procedure, you will see a warning as on screenshot below. Click on “Create trustline” button and provide your wallet password if required.
3) When your account activated you will no longer see any warning messages on Gratzio wallet page.
4) Airdrop tokens will be distributed automatically on all activated accounts. It may take up to 24 hours to get airdrop tokens on your balance after the activation of your Gratzio wallet.