Data will be pulled from your Google Sheet as a table — where the first row or column will be used as the Labels for the content; and all the subsequent rows/columns are considered the values.
In the example above, the Labels are across the top Title, Subtitle, Body and Button — with their values sitting underneath them.
By default Google Sheets Sync will assume the Labels are across the top in different columns.
If you want your Labels to be across the side in different rows instead — you can make this happen by making sure each label across the left edge is bolded and each label across the top row isn't.
Google Sheets Sync will read all the content up to the final row or column that has data in your Sheet. So avoid having any large gaps of empty space, or having any extra content that you don't want to be included. Try and keep everything in a standard 'x by y' grid.