CryptoComics is currently an invite-only marketplace. Each member is given a limited number of invites when they join. You can request more by emailing support@cryptocomics.com, or using the contact form in your dashboard.
As a member, you can invite others to follow you and join the marketplace in two different ways:
1) Share the link to your profile page. Anyone who isn't a member can sign up and follow you from the button on your profile.
2) Send an invite to them directly from the My Community card on your dashboard,
or on the Invites page.
You can see unclaimed invite codes under Pending Invites, and choose to resend that invite code or cancel the invite.