problem with installing wifi driver from source

[a dehqan <dehqan65@gmail.com>]

In The Name Of God The compassion merciful

I'll be thankfull if you guide ;
How can this error be fixed ?

# make
Kernel Makefile not found at '/lib/modules/2.6.18-4-686/source'
chmod: cannot access `compatible/*': No such file or directory
/bin/sh: line 2: compatible/kversion: No such file or directory

Makefile has been modified by generate_compatible, please run `make' again

make: *** [compatible/kversion] Error 1

Regards dehqan