Go to an existing project and click the Add button, then select Smart Contract from the dropdown menu to fill out the details for your desired contract.
Fill out the details for the Smart Contract:
Network - Network the smart contract is deployed on.
Name - Nickname for display purposes.
Address - Public hex address for the contract.
Type - Gives the contract a category and will be assigned as a tag on the object (if it does not fit into one of the categories choose other and you will be able to add custom tags to display on the object after creation).
Description - Optional to add more context to the object
Click add and you will be directed to the smart contract page.