Learn basic dos commands if you don't know them already. Linux command line is surprising similar to dos. After that, you'll learn simple things like installing software.
For most every program you download that's to be compiled, the following commands will normally work:
tar -zxvf filename.tar.gz
./configure && make && make install
If you really want to force yourself into learning, take a weekend off of your normal computer use, and try to install Gentoo linux (www.gentoo.org
) If you can follow their installation instructions, you shouldn't have a problem using command line.. ever.