Use Audacity to add audio labels to your .wav file.
Go to Export and export the audio labels as .txt file
Import the file into Spreadsheet (make a copy of the spreadsheet into your Gmail Account first) https://docs.google.com/spreadsheets/d/1GCtg8nm1GuQCTtEshgvIlZuVGCGixNnmk_yqPClQQ6A/edit#gid=16026089
Start time: change seconds into nearest whole number
Add URL OR image - both at the same time do not work
Copy all rows of the text in column I
Go to TextEditor, open CHAPTERS.json and paste it into the middle
Save the chapters.json