Multiple guides, most notably
this and
this.
I compiled using MSYS2's 32-bit MinGW mode. After issuing a "pacman -Syuu" command to make sure everything is up to date, I ran the command "pacman -Sy mingw-w64-{i686,x86_64}-ntldd-git mingw-w64-{i686,x86_64}-toolchain mingw-w64-{i686,x86_64}-SDL2 mingw-w64-{i686,x86_64}-openal mingw-w64-{i686,x86_64}-wxWidgets mingw-w64-{i686,x86_64}-libpcap mingw-w64-{i686,x86_64}-cmake mingw-w64-{i686,x86_64}-libslirp" to get everything it needed. Then, after cloning the repository with git, I ran the commands in the forum post linked as the second guide (though running "./configure --enable-networking --enable-release-build" and "make" seems to work just as well.
I copied the specific folders and files from the root directory of the pcem folder to another folder, and then copied the pcem.exe from the src folder into the root of the second folder. After making a copy of the second directory, I then opened the pcem.exe in the MSYS2 MinGW 32-bit shell and checked out every dependency using Process Explorer, and copied over all 22 dlls to the root of the copied directory. Then I zipped it up and uploaded it.
Although apparently, the latest version of PCem's upstream has a cmake solution that the TASVideos fork lacks.