How to make SVGs

And probably are halfway to the SVG information page.

But I've read it, sort of understood it. There are three ways:

1. Inkscape

2. Mapshaper

3. 'Edit directly as a text file'.

I'm using a school computer, and am not too adventurous as to downloading map-editing apps at this time, so I was wondering how to use the third option, editing directly as a text file.

Yet I couldn't find the info for it in the SVG guide.

Could some experienced JetPunk user explain how to do it? (LuckyCat recommended Dimby or Cathlete, but I guess anyone would work)

Thanks.