Usually I am using the packages from the official repositories. However, sometimes it's necessary to use a newer version, I recently had to do this with strongswan and I'm sharing the procedure for other people to try.
Get the build dependencies
apt-get update apt-get install devscripts fakeroot apt-get build-dep strongswan
Obtain and build the package
mkdir ~/work cd ~/work debcheckout strongswan cd strongswan sed -e '/dh_strip/ s/^#*/#/' -i debian/rules sed -e 's/debhelper.*/debhelper,/g' -i debian/control dpkg-buildpackage -rfakeroot -uc -b