... I don't really know where to begin because the entire process feels like black magic to me: calling out incantations found on internet tutorials and hoping. Is there a straightforward way of installing c++ libraries that 'just works'?
It is by
no means "black magic". It is actually quite simple. Let me try to explain:
First you get the source code; either by simply cloning the git repository or by extracting some archive file (zip file, tar+gz file or whatever).
Then you use cmake (with appropriate options) to generate build files (nmake files, make files, Visual Studio Project files or whatever) that suit your environment/compiler.
Then you use your native build tools to build the library according to the files cmake just generated for you.
Once the library is compiled, you install it - again using your native toolchain in combination with the build files that cmake already generated.
Then you use the library.
On a Linux system, the above is usually as simple as:
git clone (or "git pull" if you already have a clone)
cmake
make
sudo make install
Takes all of 5minutes - how much easier do you want it?
The
official tutorials even explain it in great detail (much more than I do here).