3 column theme or widen widget area

Been trying to edit my Buddy Press twenty ten theme to widen the right widget area without any luck. Below is my style css and instructions which I followed. It is without the changes as they diddnt work or i did not do it correctly.Steps I followed and my original style css are below. Be even happier to go to a three column theme, no luck on that either. Any help would be appreciated

“This is what I was following,, seemed pretty straight forward but diddnt work.I did notice some what I thought to be unusual things in my style css.”

Customizing the WordPress Twenty Ten Theme.

#container {
margin: 0 -300px 0 0;
}
The Twenty Ten theme uses a negative right margin of 240 pixels for the #container class. To increase the size of the Twenty Ten theme sidebar from the default 220 pixels to 280 pixels, subtract (we are working with a negative number, here) an additional 60 pixels, for a total right margin of -300 pixels.

#content {
margin: 0 340px 0 20px;
}
Likewise, the right margin of the #content class also needs to be plussed-up by 60 pixels, for a total of 340 pixels.

#primary,
#secondary {
width: 280px;
}
Finally, the #secondary class needs to reflect the new sidebar width of 280 pixels, as shown above.

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