how do you inflate this? Is it easy?

Blowing into an air mattress is actually not the greatest idea. It'll inflate the pad faster, but it's not advised. There is moisture in exhaled air. Eventually, this will soak the insulating portion of the mat--this can reduce the insulating material's effectiveness as an insulator. If you plan on operating in cold climates, the moisture can actually freeze. And above all, moisture adds unwanted weight. Over time, it will make a difference.

Yes it's easy, you blow in it. Like every other inflatable object you've encountered.-----------You lay it out open the valve and it self-inflates almost all the way, you then top it off by blowing in it and close the valve.-----------Remember when you first buy the pad you need to open the valve and leave it open for at least 24 hours. It's not going to inflate immediately. After doing this, it should inflate in about 10 minutes. It needs to be stored, if possible, unrolled and with the valve opened for the best inflation performance. They won't ever lose their ability to inflate, even when rolled up, it will just take a lot longer. It's ok to blow a few breaths in after it's inflated depending on how firm you want it.