--- a/ContributingCode.wiki	Tue Jan 19 18:59:12 2016 +0000
+++ b/ContributingCode.wiki	Tue Jan 19 19:29:26 2016 +0000
@@ -52,11 +52,23 @@
 
 = How to export your changes so that we can use them  =
 
-TODO: diffs, exported patches, public repo clone, etc.
+== Public Repository ==
+If you setup a public repository e.g. at github, bitbucket or on your own server, just push your commits there.
+Then send us the links to the commits/bookmarks that you want to go into the official repository!
+
+== Export mercurial commits ==
+With {{{hg export --git -r commitid1 -rcommitid2 ... > my.patch}}} you can export the commits specified to a patch file.
+
+Note: the {{{--git}}} argument is used, so that binary file changes (e.g. changed pictures), are included in the export.
 
-== Public Repository ==
-If you setup a public repository e.g. at github, bitbucket or your own server, just push your commits there.
-Then send us the links to the commits/bookmarks in question!
+== Creating a file containing the code differences ==
+You can use the {{{diff}}} command (if available on your platform) to output the differences between e.g. the original code and yours.
+Save that into a file and send it to us.
+Note: Don't forget to also send binary files, so pictures/etc. that you changed - since usually {{{diff}}} will only cover text changes!
+
+ 
+
+If you have a mercurial clone of the official repository but you don't want to locally commit your changes for some reason, you can use use {{{hg diff --git > my.diff}}} to generate a diff file containing changes to code and binary files.
 
 
 = How to let us know that you want your commits/patches to go into the official repository =