You can pay your Stoic management fee from any wallet that supports ERC-20 transfers.
Each crypto wallet has different interfaces the general flow is the same:
Make sure to have enough ETH in your wallet to pay for the transaction's gas;
Select USDT as the ERC-20 token to transfer;
Enter the address for fees you receive from Stoic as the destination (please double-check this, if you send to a wrong address there is nothing we can do);
Select the appropriate gas limit (an ERC-20 token transfer requires 65,000 units) and gas price (check https://ethgasstation.info/);
Confirm the transaction.
Once the transaction is mined and added to the blockchain, Stoic will recognize it and you'll see it in the app.