Basically using diff

Published: Wednesday, Dec 26, 2007 Last modified: Monday, Nov 23, 2020

I have been using diff ! :)

diff -N -r -u bins-1.1.21 bins-1.1.21.bug/ > bins.patch

N esp. if your patch includes new files r for recursive u for human readable

Have a look at the patch to be sure of order. Plus signs (+) should be the changes you want.