1. Set the WCSTOOLS environment variable pointing to the location of your WCSTools distribution:

   Bourne shells $ WCSTOOLS=/path/to/wcstools $ export WCSTOOLS

   C shells % setenv WCSTOOLS /path/to/wcstools

   Alternatively, the environment variables WCSTOOLS_INC and WCSTOOLS_LIB may be used.

2. perl Makefile.PL
3. make
4. make test
5. make install

If compilation fails, please make sure the version of WCSTools you're using matches that listed in README as a requirement for this version of the module.

If on an AMD64 system, and building the module produces errors of the form

/usr/bin/ld: /path/to/wcstools-3.8.1/libwcs/libwcs.a(imsetwcs.o): relocation R_X86_64_32 against `.data' can not be used when making a shared object; recompile with -fPIC

then this indicates that you should add -fPIC to CFLAGS in the wcstools libwcs/Makefile, make clean there and recompile before attemping to build the Perl module.