first master the strumming pattern as already said here. then think of the words in your head as you strum. then maybe hum the words or tune as you strum, then try fitting the words in as you strum, then enjoy...
one more thing, it mite be worth trying to play along with a recording of the song as opposed to just listening to it, that way you can get a better feel of how everything fits together
Murder For a Jar of Red Rum!
failure 2 prepare, is preparing 2 fail, :(
if you keep doing things the way they've always been done, then you'll keep getting the things you've always got