make.conf stores system-wide build settings that apply each time you run make. Copy example:
cp /usr/share/examples/etc/make.conf /etc
Compile the source code specific to your CPU:
CPUTYPE?=native
It is recommended uncomment the following: CFLAGS, CXXFLAGS, COPTFLAGS.
# 2 jobs per CPU
MAKE_JOBS_NUMBER=4
# KNOBS -- A list of popular knobs and their descriptions
# http://svn.freebsd.org/