Step 1: Head to https://app.polkamarkets.com/
Step 3: Click the "Connect Metamask" button on the top right corner
Step 4: You might be prompted to change to the Moonriver network
If so, just click on "Change Network" and switch to accept the Metamask prompt to switch networks.
You'll also be prompted with adding Moonriver to your network list if you haven't done so before.
Step 5: All set! You're connected and you're ready to make predictions 🎉
Watch the video for a better understanding of how to connect your wallet to Polkamarkets: