[newbie] Where's the Sound?

[Steve Leseman]

What do I need to do to get sound working? 
It gives a sound mixer error, and says to type: "a+rw /dev/mixer " with 
a tiny, tiny x behind and above the last r. It says to do this in root, 
I assume in the console. I tried it in root, except I had no idea how to 
recreate that tiny x. All I get is an error message - command not found, 
or something like that. I have a Sound Blaster card. Thanks.