How to draft new updated site while leaving existing site in production?

[AmadorCompany]

We are planning to upgrade and add ecommerce. But, we want to do this over several weeks so we can draft the new site and make edits before pushing it live. Meanwhile we want to leave our existing site in production, undisturbed while we create the new updated site. 

 
Is this possible?  If so, how do I have a working draft copy of our site to build the ecommerce with (while leaving the current site in production)?

Thanks!

[Bernadette3 · Accepted solution]

What are you going to be updating? The content or the theme/layout? You can create a new site to change the layout, but you wouldn't have access to the business features. I think the easiest way would be to create hidden pages in the website and once you have completed the project you can replace the old pages with the new.

[brittanyaltmann]

When you replace the old pages with the new ones, does it effect SEO? Does it transfer the valuable "link juice" attached to the page?

[Bernadette3]

As long as the page name stays the same it shouldn't, although any type of change to a site could yield some difference in SEO results. Once Google recrawls the site and indexes the new information there could also be a change (for better or worse) depending on the content on the page. 

[Bernadette3]

If the page name will be different you can always setup a 301 redirect.