On the payment page you will see you how many GPUs you have in your farm, what is your price per GPU and your monthly expense. There is a unique ETH deposit address. By sending ETH to that address you can add balance to your account. ETH you sent will be converted from the current rate (ETH/USD) and will be added to your account in $. You will be able to see your deposit transactions in the payment history section.

Did this answer your question?