Make patch from current diff in module

Want to make a quick patch for changes you made in some contrib module to submit it to d.org ?
Write down this and submit the file

git diff  > my_changes.patch

if you want diff from staged files use

git diff --cached > my_changes.patch

To change paths of the patch use

git diff --src-prefix=a/new/ --dst-prefix=b/new/

like stated here