I don't know about all of you, but I have been very disappointed in the stickiness of my Cricut Mats. Half the time they don't seem very sticky when I buy them and they surely don't stay sticky very long. I've tried the washing and letting it air dry trick - it cleans the fibers and stuff off the mat and helps for a while but really doesn't restore the sticky. Same with the baby wipe trick.
As for trying to apply new adhesive, I've tried the wide 2-way Zig adhesive but it was hard to get a nice even coat - seemed like I got too much on and ended up ruining a mat. Then, I tried taping off the edges and using a repositionable spray adhesive - this gave a pretty good result but was messy.
Last week one day, browsing various forums, I found another method and it has produced, BY FAR, the best result. It's economical - 4.99 for the glue, you mix 50/50 with water and since it is thin, you don't use much. You can paint it on with one of those cheap disposable foam brushes and it is easy to get just the right amount. I did one mat as a test on Saturday night. I cut all day Sunday on it, did the Nurses cuts this morning, and IT IS STILL STICKY! What is this miracle glue? Aleene's Tack-It Over and Over. Here's the video.