The first time you publish you will need to choose a name. This will create the link to your site (what you see in the address bar).
Keep it simple and relevant, but because many of the links will already be taken you may also need to get creative.
I recommend using the following format: firstname-lastname-portfolio

This is what everyone else will see. It is now live on the internet. This is also the link you need to share on the next page.