The edge pieces are still connected from molding the mats. There are 2 middle pieces and 4 corner pieces, 2 of them have a logo on them make sure they are on the same side. Place down the mat so the corner tiles are in the corners and the middle tiles are in the middle.
For a seamless layout make sure the middles pieces and corner pieces are placed down in the correct way.
Once placed down in the correct way you can assemble your mat.
If you have more than one mat and like to add that to get a larger surface make sure to remove the edge pieces of the long side of the mat and the bottom and top row. Then line it up with straight edge pieces and fit your mats together.
Disclaimer, connecting two or more mats together has an effect on the design.