Originally Posted by
ptquilts
does it matter which side of the cutter goes against the ruler?
It depends on your cutter - most are "ambidexterous" and can be used from either side, but some have a blade guard or other fastening parts that would get in the way on one side or the other - but usually those ones can be held with those parts either on the right or the left. So basically, it only matters if your cutter has parts that get in the way.
I'm right-handed, so I normally cut with the ruler to the left of the blade and the blade riding against the right-hand edge of the ruler (which means the ruler is against the left side of the blade/cutter).