Child Theme; doing it right..?

Hey everyone (again!).

I’ve been trying to figure out how to preserve my alterations to the twentyten theme all day. I spoke to someone earlier who advised me to just create a new theme entirely because I’d so heavily edited the original twentyten theme (which is why I probably wouldn’t want to do a child theme at this point). Trouble is, I’m so new to all of this I don’t even know what to search for when looking to figure stuff out. :\

In creating a new theme, would I just copy ALL the various .php and .css files from my custom version of twentyten and put them in their own directory? Or is there something else I need to do? Would I need to make a special header for the .css file?

Grateful to anyone who might be able to let me know if I’m on the right path or not.

site is myvibrantliving.com