Remember to leave the 1/8" gap against the walls for expansion as mentioned earlier. This can be covered up with the base molding once you're done.
Also, wear shoes and long pants.
Trust me..... I had two incidents, one where I snapped two pieces together only to entrap a piece of skin just below my knee in the joint...... you wanna talk about painful and phuckin funny all at the same time? You've never seen anything like me jumping up shouting obscenities taking most of the floor with me!
incident 2 was just a piece of sock.... forever trapped in a joint. I'm the only one who notices it or even knows where it is. But every time I see it it reminds me of incident #1.