Oh - Gus, I think I have misunderstood you - I am not computer savvy - but here is my Husband who will try to explain what you need.
Hello Gus Pete here - If you are trying to place a link to your design wall as your signature you have to use the free web space allocated to you by your service provider. Or if you don't have any you will need to buy some for an annual fee from a web space provider. When you have some web space you then have to create a web page with your wall info loaded into it. Then this page will have an address made by you for your web page and this address is what you use as a signature. Like Dots at our web provider talktalk here in the UK.