How to put an existing NFT on the market

• Go to your Profile
• Click on the desired NFT.
• Select the blue Sell button at the top right of the screen.
• Pick Fixed Price if you want to sell for a specific price, or Timed Auction if you want people to bid on your NFT.

Charges:

• OpenSea charges an account initialisation fee for your first listing.
• Ethereum transactions have "gas fees."
• For an offer, the seller pays the gas fee.
• For fixed price sales, the buyer pays the extra cost.