The following outlines howto apply a patch to CLISH

$ tar zxf clish-0.7.1.tar.gz
$ cd clish-0.7.1
$ patch -p1 < ../clish-0.7.1-foobar.patch

At this point you will then have a patched source tree.

NB. the -p1 option is used to enable you to apply patches irrespective of the original directory name of the patched source tree.

best regards
Graeme