diff --git a/_episodes/01-tooling.md b/_episodes/01-tooling.md
index dd30895d53b52e33c2ca8eed0685a6732f4fd5d3..c587970e8c72a8a8ef134b5c8e6729d1c12fd8fb 100644
--- a/_episodes/01-tooling.md
+++ b/_episodes/01-tooling.md
@@ -116,15 +116,15 @@ The [lesson template]({{ site.template_repo }}) does *not* include `_config.yml`
 since each lesson will change some of its value,
 which would result in merge collisions each time the lesson was updated from the template.
 Instead,
-the [template]({{ site.template_repo }}) contains `_config_template.yml`;
+the [template]({{ site.template_repo }}) contains `_templates/_config_template.yml`;
 authors should copy this file to create `_config.yml`
 and then edit values in the top half.
 
 The [template]({{ site.template_repo }}) also contains `_config_dev.yml`,
 which overrides some settings for use during desktop development.
 The Makefile that comes with the [template]({{ site.template_repo }})
-adds these values to those in `_config.yml` when running a local server,
-so that `make serve` previews the generated site at <http://127.0.0.1:4000/>.
+adds these values to those in `_config.yml` when running a local server
+(see [below](#previewing)).
 
 ## Collections
 
@@ -139,6 +139,22 @@ we store files that appear directly in the navigation bar
 (rather than under a pulldown menu)
 in the root directory of the lesson.
 
+## Previewing
+
+[Jekyll][jekyll] can be used in two ways:
+to compile source files into HTML pages in the `_site` directory,
+or to do that and also run a small web server at <http://127.0.0.1:4000/>
+so that the pages can be previewed.
+We strongly recommend using the latter,
+since it ensures that inter-page links will work
+and extra resources (such as glyph icons) will load properly.
+
+The Makefile in the root directory of the project has commands for doing both:
+`make site` builds files but does not run a server,
+while `make serve` builds the files and runs a server.
+(It also re-builds the site whenever it notices changes in the source files.)
+Run `make` on its own to get a list of commands.
+
 [github-importer]: https://import.github.com/
 [jekyll]: http://jekyllrb.com/
 [jekyll-collection]: https://jekyllrb.com/docs/collections/
diff --git a/_episodes/03-organization.md b/_episodes/03-organization.md
index 1cc0bf4e509200f6b8094e5db6fd0cf271e3f959..f2fbec64a3d2214183e593fd6b5e14b248d26a7d 100644
--- a/_episodes/03-organization.md
+++ b/_episodes/03-organization.md
@@ -54,6 +54,19 @@ which should *not* be modified:
 *   `LICENSE.md`: the lesson license.
 *   `Makefile`: commands for previewing the site, cleaning up junk, etc.
 
+## Template Files
+
+The `_templates` directory contains files that need to be customized for each lesson:
+
+*   `CONTRIBUTING.md`: contribution guidelines.
+    This file should be copied into the root directory,
+    and the `issues` and `repo` links at the bottom of the file must be changed
+    to match the URLs of the lesson.
+*   `_config.yml`: [Jekyll][jekyll] configuration file.
+    As explained [earlier]({{ site.root }}/01-tooling/#configuration),
+    `_templates/_config.yml` must be copied into the root directory
+    and edited so that its links and other settings are correct for this lesson.
+
 ## Common Files
 
 Most lessons will contain the files listed below.