We will be happy to describe precisely how to measure when we conduct an online planning session once you have emailed us digital photos. Notice that the client (below) showed us EVERYTHING in one photo which makes planning easy. "Close-ups" do us no good and are discarded.
We commonly ask for "daylight" heights & widths of a given opening described in the photo, but it will depend on how your panels are configured. Our planners will encourage you to consolidate panels whenever possible as curtain panels can span more than a single opening. It is to your benefit to consolidate panels because it SAVES YOU MONEY and minimizes the number of fasteners.