diff --git a/tools/plan-viewer/README.md b/tools/plan-viewer/README.md
index 72b4fef..334e2c1 100644
--- a/tools/plan-viewer/README.md
+++ b/tools/plan-viewer/README.md
@@ -5,3 +5,13 @@ A static HTML viewer for `plan-runner` JSON files (the fixtures).
 ### Usage
 
 Open [`index.html`](index.html) in a browser, then drop a JSON file from [`crates/plan-runner/fixtures/`](../../crates/plan-runner/fixtures) onto the page.
+
+Alternatively, you can run the commands below to serve the viewer locally:
+
+```sh
+make viewer
+```
+
+Then open the following URL in your browser (replace `two_atom_join.json` with the name of the plan you want to view)
+
+http://localhost:8000/tools/plan-viewer/index.html?fixture=../../crates/plan-runner/fixtures/two_atom_join.json