1.  Once you have made changes to website it is best to Preview your website on your machine first. Enable Rebuild All via Settings then Preview the shop to external browser

2. When you are happy with the changes and are ready to publish then Click on "Publish your website on the Net" from the Publish menu in the toolbar

3. Publishing options

To Publish the changes to your website, make sure the box "Publish All" is NOT ticked

To Publish the whole website again then Click "Publish All" box in the window below