If you're a veteran Cricut owner, these tips probably aren't new to you. But if you're just discovering the wonderful world of electronic cutting, the information below will help you save money by making your mats last a long, long time.
Before pulling off the clear acetate covering on a new mat, use a Sharpie and mark "TOP" on it. Then after use, you can put the cover back on correctly and it won't stick to the mat. It's important to keep these covers on when not in use so that the mats don't pick up dust and lint.
A new mat will be extremely sticky. To "condition" it so that it will not ruin your paper, pat your hands all over the surface. I like to keep 3 or 4 mats ready to go at varying degrees of stickiness. Thin papers go on the least stickiest, heavy cardstock or Grunge go on the mat with the most stick.
It's important for a good cut to keep bits of paper off of the mat. I use the Cricut spatula to lift off cut pieces. Then if any residue is left behind, will use a handy little scraper I picked up at a business expo. It's made to go on your keychain to scrape your car windows but as soon as I saw it, I knew it'd be perfect for scraping mats. At the end of my cutting day or if the mat gets "fuzzy" I'll take a baby wipe and clean the mat. When the baby wipes just don't seem to bring the stick back to the mat, I will simply scrub in the sink with soap and water.
Finally when even a sink scrub won't bring the mat back to life, I use International's "Stick & Spray". You first remove any remaining stick with "Stick Away". Once the mat is totally clean, tape off the sides with masking tape and spray on a coat of "Stick & Spray". This will make your mat stick like new. I have heard of people also using a mixture (1:1) of water and Alene's "Tack It Over & Over" glue or a Zig glue pen to re-stick their mats. I haven't tried either of those methods so I can't tell you what I think. One thing I do know is that I have used the same mats for 16 months and have only sprayed two of them once. I did have to retire the oldest mat I owned but only because the edges curled and cracked. I then used it as a stamping mat.