this question is a bit general ;). OS version would be a nice detail. I
would suggest installing slime (http://common-lisp.net/project/slime/)
the rest is easy.
For windows a .emacs could look like:
(add-to-list 'load-path "C:\\home\\slime\\")
(setq inferior-lisp-program "c:/clisp/full/lisp.exe
For unix flavours change accordingly.
Setting up asdf/asdf-install is somewhat more complicted at least on
windows. Searching c.l.l or google will provide enough informations, though.
Why don't you state what kind of operating system and cpu architecture
I am using windowsxp