-Think about whether your change requires updating the documentation
-(both manuals and doc-strings). If you know it does not, mark the NEWS
-entry with "---". If you know that *all* the necessary documentation
-updates have been made, mark the entry with "+++". Otherwise do not mark it.
+Doc-strings should be updated together with the code.
+
+Think about whether your change requires updating the manuals. If you
+know it does not, mark the NEWS entry with "---". If you know
+that *all* the necessary documentation updates have been made, mark
+the entry with "+++". Otherwise do not mark it.
+
+Please see (info "(elisp)Documentation Tips") or
+https://www.gnu.org/software/emacs/manual/html_node/elisp/Documentation-Tips.html
+for more specific tips on Emacs's doc style. Use `checkdoc' to check
+for documentation errors before submitting a patch.
+
+** Test your changes.
+
+Please test your changes before committing them or sending them to the
+list.
+
+Emacs uses ERT, Emacs Lisp Regression Testing, for testing. See (info
+"(ert)") or https://www.gnu.org/software/emacs/manual/html_node/ert/
+for more information on writing and running tests.
+
+To run tests on the entire Emacs tree, run "make check" from the
+top-level directory. Most tests are in the directory
+"test/automated". From the "test/automated" directory, run "make
+<filename>" to run the tests for <filename>.el(c). See
+"test/automated/Makefile" for more information.