After driving my car for the first time this summer, I quickly discovered the importance of floor insulation. It's like driving a Libby's bean can on a barbecue! After researching some older posts, I decided on Fat Mat. I bought the 100 sq. foot kit, that includes a little wooden roller. I want to do the firewall and the floor with 2 layers. I've never used this stuff before, any tips or tricks to make the installation go smooth?