Click on "Recharge" button on the upper left corner on your monitor display.
Click "Recharge" again to confirm.
Choose OneCard Recharge Method; confirm that account logged in was right, also select which Server you want to Recharge to; select the amount you want to Recharge and click Recharge.
Sign in to your OneCard account, and click "Pay".
Click "Yes" on the next page to complete Recharge.
You will be directed to this page.
And finally a confirmation saying that your Recharge has been completed.