Create / pre-register an account at The Sandbox, so they can play your experience when it releases in the metaverse and purchase your NFTs during the NFT drop.
Sign up for newsletters from The Sandbox, so they can get updates about the Game Maker Fund projects, including yours, via an email newsletter.
Follow The Sandbox’s official social media and/or Discord server, so they can get updates, including about Game Maker Fund projects like yours.