Here's some ideas:
Blades can be sharpened with heavy duty aluminum foil. Simply cover
your mat with the foil. Create a file with several straight lines, a couple of
circles, and a few squares. Set the speed to slow or medium in case the
foil comes loose from the mat and you need to quickly abort. Set the
thickness to 1. Repeat with all three blade caps.
When a blade is slightly dull or you have a thick cardstock and
need to cut twice, try copying/pasting the image on the screen on top of
itself. The cutter will then automatically cut it twice.
Also, pieces of lint can occasionally get caught up in the blade.
Remove the cap and check the blade under a magnifying glass to see if
any fibers are present.
I will definitely be doing the aluminum foil trick! And how smart to double the image to automatically cut twice! Brilliant!