diff --git a/README.md b/README.md
index d9a5b89ab5861cf918175f8e050ac95602e187ca..3493cd332df04c9460c1ba0626bbf1a869b640da 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,12 @@ rustup update nightly
 rustup override set nightly
 rustup target add thumbv7em-none-eabi
 ```
+When cloning use `--recursive` to get the submodules, otherwise update them
+afterwards:
+
+```shell
+git submodule update --init --recursive
+```
 
 Check out this repo's submodule (the C firmware).