Here is a tip we have used a lot in our community, for people who want to work on their Pages in private.
You can work on creating your new Pages and Tiles while your Overview page is live. Follow these steps.
Convert the group to Activity + Pages
Click on the gear icon and Manage > Settings.
In Advanced Options, select Activity + Pages. Click Save at the bottom left of the page.
Create a new page
Click on the gear icon Manage > Create a page and call it e.g Main Page (you can edit this later) and OK.
You have to add one Tile before you are able to save the new page. Click on Collaboration > Document Viewer just as a placeholder tile that you can change later. Save the page.
Save the URL of the new page
Now, this is the important part. Once you have saved the new page, click at the top on the URL of your new page and copy it. Copy it to a new tab, bookmark it or send it to yourself by email. Keep it somewhere so you can find it. This is what you will use to come back to later, to work on your page while your Overview page is live.
Convert the group back to Overview
Click on Manage > Settings > Advanced Options and select Activity + Overview (or Overview depending on what you had before), and OK. Save. Now your group will be back to normal, with the Overview page live.
Note: after saving Activity + Overview you might be taken to your Activity page but don't worry, the Overview on the left is still the 'landing page'.
Build your new page at your leisure
Retrieve the URL of your new page (the one you copied or bookmarked), and you can now edit the page by clicking on the gear icon in the top right hand corner of a tile to put the page into edit mode. Don't worry about any impact to your members. They will still see the Overview page. Also, now you can open a second browser and refer back to your Overview page and widgets side by side while you work on building your page with corresponding Tiles.