diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 1722da6d5..62cf10c68 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -7,6 +7,10 @@ Contribution are most welcome! All `tldr` pages are stored in Markdown right her
 
 *Note: when submitting a new command, don't forget to check if there's already a pull request in progress.*
 
+## Setup
+
+When setting up a brand new fork, run `make setup` to install the git pre-commit hook that will rebuild the index every time you commit your changes. You can also rebuild it manually by running `make index`. The script requires Ruby to run. Make sure you have the index in place as we will need it as part of your commit in order to pull in your changes.
+
 ## Guidelines
 
 Note that `tldr` is focussed on concrete examples.