If you have a new distribution of Linux, do these modifications to these files in your home directory. They take effect after next login.
~/.bashrc:
alias ls="ls ‐‐color"
~/.cshrc:
alias ls 'ls ‐‐color'
You may also want to do an ``eval `dircolors
$HOME/.colourrc`'', to get your own colours. This file
is created with ``dircolors -p >$HOME/.colourrc'' and
is well commented for further editing.