Help with a link

[elstager]

Hi, I'm new and while setting up my profile I came across the following option:

For those members wishing to share a link to the thread documenting the build of their aquarium. Add the URL (link) to your tank build thread here and you will automatically get a "My Tank Thread" badge! Your new badge will also be a LINK to your build thread!

Can anyone help me with this? I don't have a url for my tank hobby....

Thanks!