Your game must have the ability to run in a browser, so you are able to connect the CNAME you want.
Submit an issue on github here, and label it with the "new request" label. In your request, include the SUBDOMAIN you want (it can be CUSTOM.myonlineurl.com or CUSTOM.io.tixte.com) and what CNAME you need attached to that subdomain.
After you submit the request, it will be left pending until a team member of Tixte can approve or comment on it. If we change the labels on it, what they say is what step of the verification proccess we are on for that domain.
Now that your game is on Tixte IO tell people to go to your custom domain! TIP: You can also learn about adding your game to OUR gaming platform called Tixte for even more visits. Learn more about that here.