Advice wanted: I want to do a complete revision of my Squarespace web site. Where to start?

I've had a Squarespace-hosted website for several years dedicated to my photography (www.belasphoto.com), and did a minor revision of my original design about three years ago. It's high time I do a major change to modernize my pages and emphasize my photography sales (and artistry). My goal is to have a new site up and running within 3-4 months, so there's time to spare in planning.

With that in mind, I ask for advice on where to start the process of redesigning my site? I want to find a new web format, where should I go on Squarespace's pages to look for a format conducive to photography? Can any of the migration from my old pages to the newly designed ones be automated to ease the transfer to a wholly new design? Obviously, I've missed a ton of other important questions to ask, so feel free to add them to my list.

If you have a minute, all I need at this point are some urls that point to where on Squarespace to begin the process of making a new site and migrating from my present one. Once I've read and digested their information, I'm sure I'll be back with more questions.

Thank you.

To redesign site, you can use Preview Template Feature.

https://support.squarespace.com/hc/en-us/articles/205815598-Switching-templates-in-version-7-0

If you want to change to 7.1 version, you will need to create new trial, design site, copy content from current site to 7.1 (copy manually), then transfer subscription to 7.1 site