You should start by installing Macports. Afterwards start a terminal session and run
sudo port install sumo
While this will install a SUMO version you maybe do not want to use, it will pull in all dependencies you need.
If you want to build from a repository checkout you should additionally do
sudo port install automake autoconf
If you wish to use clang rather than gcc for compilation do:
./configure CXX=clang++ CXXFLAGS="-stdlib=libstdc++"
Thanks to all MacOS builders for sharing their insights.
By building SUMO from sources you can be sure to make use of the latest version. For detailed instructions, see building with Homebrew.