After this you'll see a transaction as you wait for your token to be staked. Once staked it will appear in the farm and you can unstake it at anytime.
Important Note: When you deposit your SLP for farming, the exchange.sushiswapclassic.org/#/pool page no longer sees it. That page only scans your wallet to see if you are holding SLP tokens. So that page will say "No Liquidity" - however you do still have your tokens and you are still earning the 0.25% trade fee, it is just currently deposited in the farming contract and so not detected.