Okay, a quick note on what to do with two mats that meet up with each other.
[picture from Mymatting.com]

Overlapping is a great way to deal with matting that meets up, some people add a little two-sided tape (not really needed, but a nice extra if wanted). If for some reason your mats do not match up you will have to cut, simply do an over lap then using a straight edge cut down through both mats. After cutting down the length go back and pull out the cut off pieces and lay the mats back down and they should match up right on your cut lines. Most people I talk to are not that fancy and just lay the mats overlapping and leave it at that. Some do not even have the mats that close to each other and the do not have to worry about any of this. Happy garage floor laying / installing.