Note the new domain name is: nomasks.info
You can print your exemption badge from the gov.uk website above. Alternatively you can buy one from a variety of sellers. (Remember: You don't have to wear a badge, but it may make it easier to claim exemption)
(Remember that you do not need to explain your reason, so badges that explain this are not necessary - you have the right to keep the details of your reason private).
Hidden Disabilities: https://hiddendisabilitiesstore.com/hidden-disabilities-face-covering.html