Go to the BarnBridge app at https://app.barnbridge.com/smart-yield
Connect your wallet to the platform.
Click on the "Pools" tab.
Select the pool (based on the jToken you have) and click the "View pool" button.
On the new page, click on the switcher below "Enable token" to enable interaction between the smart contract and your wallet.
Enter the amount of tokens you would like to stake or hit "Max".
Click "Stake" at the bottom of the page.
In the pop-up window choose the transaction processing time and click "Confirm your deposit".
Confirm the transaction in your wallet, pay gas fees, and wait.