There are two different types of SwissTrax edge pieces, looped and pegged. The difference between the looped and pegged edge pieces is how they attach to the normal tiles.
This is the looped edge piece:
This is the pegged edge piece:
Which one you get depends on which orientation you lay the tiles down. Matt likes to have the looped edge pieces for the garage door opening. Using the looped edge pieces will be more secure because they will be held underneath the tile connected to it. How you would start setting it up is to start at the garage door and work your way back with the looped edges towards the back of the garage. This allows you to press the tiles down as you work back rather than having to lift up the tiles to place them.