After connect to the wallet, you need to choose your broker and bind the service relationship.
If you already have the Broker Code (you can ask your Broker for the code), fill the correct code in the blank area, then click "Confirm".
If you don't have the Broker Code, just click "I don't have a code..." button.
There will be a list for all existing Brokers, classified by Language and Community.
Choose a Broker you like, then click "Set as my broker".
After submission, your wallet address will be bound to your broker, you can click on "Trade" to begin your trades.
You don't need to choose Broker again after binding your relationship.