Yet another reason why I love Squarespace is that it automatically generates a sitemap for your website.
A sitemap is important to you and your online presence once you are semi-established and concrete on your brand, vision and site as whole because it serves as an indexing agent for google and other search engines. I recommend NOT worrying about this aspect of your website (along with other digital concerns like SEO) until you are SOLID on who you are, what you offer and HOW speak to your clients and people.
If you already have a Squarespace site you can locate your .xml site map @ http://(enteryoursitename).com/sitemap.xml - they have already taken the guess work out of generating a Google friendly sitemap. (Lord, I love Squarespace).
Your Next Steps....
Create and log into your Google Webmaster Tools account
Add your Site to your account dashboard + verify ownership (click here for a SUPER SIMPLE Squarepace tutorial on connecting your Google Analytics tracking code)
Within your Google Toolmaster Dashboard you will want to test and then submit a sitemap. Click here for Google instructions for doing so.
That's it. The Google will need sometime to refresh and update. In a few days check back on the interwebs to see an updated indexed site map for you digital home.