While I was still at comprehensive school (i.e. 1979), I wrote at least two editions of
Wargaming Book. As you can see it might go some way to explain why in French I attained the giddy heights of CSE grade 2 (equivalent to grade D for O levels and (according to wikipedia) grade 3 in the modern GCSE system.
The rules were based on my reading up to that point and so was based on both the SPI hex war games of the time plus a hardback copy of (I believe the first edition) of Setting up a Wargames Campaign by Tony Bath that was available from my local library.
The book includes a small campaign (using the map on the front cover) and I do remember then creating a huge map attempting to use a large hexagonal nut to draw the hexagons on a 6 foot by 4 foot board which had also been used for my model railway.
The second edition (written, according to the writing history, in November 1979) was more of an attempt to clean up the layout of the first edition though it did reveal some of my interest in electoral systems by having a section on different ways of ruling a country, two of which focused on the difference between first-past-the-post and proprtional representation!
I have created a pdf of the first version of the book (the version whose cover is shown in the image). This pdf does NOT include pages 40 to 47 as those pages are covered by the copyright for Setting up a Wargames Campaign to which I do not have the rights.