Create a directory that only contains the icons that you want in the font.
This step is not needed, but complex SVGs might confuse FontForge. You can use GIMP and Inkscape, however to my knowledge only Inkscape can be automated.
Run the following command:
inkscape *.svg --actions="select-all;path-flatten" --export-type="svg" --export-overwrite
This command will produce a [filename]_out.svg file, which should have less render instructions.
You may call svg2font like this:
python svg2font.py --path my_svgs --font_name my_cool_font
You now have a font that contains all your svgs, starting at \uE000.
The stdout should give you a clear idea of where each icon is.
You can append --cpp_map
if you desire to use the font in a C++ app, and you want a header that keeps track of unicode indices.
If your SVG paths have the wrong winding order then you should pass --correct_direction auto/always
depending on what works better.