Looking at it quickly, if you want to make it 20 blocks as it shows on page 2, for the blocks you would need:
Fabric 1 1 yard
Fabric 2 1 3/4 yards
Fabric 3 2 3/4 yards
I usually get a little more of each "just in case" so I would add about a 1/2 yard to each fabric. That would make it 5 1/2 yards before adding extra, or 7 yards if you did.
I would double check these numbers in the morning though. Time for bed now.