Click the 'Update Profile' button on your profile page (see graphic 1 below). You will need to be logged in to AmeriCymru. Find the 'Profile Biography' field on the page (see graphic 2 below). This step is not obligatory. After all you may wish to use your profile page for some other purpose. BUT if your main purpose is to sell on AmeriCymru it is well worth adapting your home page as a store 'front page'.
Here you can add pics, videos. text and links. The more attractive and engaging you make your profile bio the more you will sell. A good profile bio also makes it easier for us to promote your store.
If you want to add some styling you will find some ideas here:- Simple CSS Tricks