- Log into OKX.
- In the top right corner of the screen click Assets > Withdraw.
- Select to withdraw ETH using On-Chain into the ETH-Optimism network and click Continue.
- Configure SMS authentication if you haven't already done so.
- Enter your address and the amount to withdraw. Then click Continue.
- In the withdrawal configuration panel, click Send for both the e-mail and the SMS.
- Enter the two confirmation codes and click Confirm.
- Congratulations, in a few minutes you'll be able to use OP Mainnet.