diff --git a/tools/CHECKLISTS.md b/tools/CHECKLISTS.md
index f4afacf8f..1a75384e7 100644
--- a/tools/CHECKLISTS.md
+++ b/tools/CHECKLISTS.md
@@ -12,7 +12,13 @@ The following checklists are there not to forget things ... to be continued.
 
 # Add language
 
-- add `MessengerProj/src/main/res/values-<LANG>/strings.xml`
-- add copy routine to `tools/txpull.sh` and `tools/txpush.sh`
+1. add `MessengerProj/src/main/res/values-<LANG>/strings.xml`
+2. add copy command to `tools/txpull.sh` and `tools/txpush.sh`
 
+# Update source languges
+
+1. modify `MessengerProj/src/main/res/values/strings.xml` as needed, commit them, but do not push them yet
+2. call `./txpull` from tools-directory
+3. `git push` (after the pull to avoid a source-pull from transifex removing the translations due to unknown source strings)
+4. call `./txpush` from tools-directory