Update INSTALL.md

1 files changed, 10 insertions, 3 deletions

diff --git a/INSTALL.md b/INSTALL.md
index 32805159..6be1a1ac 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -65,12 +65,19 @@ nixpkgs#crystfel` to have all CrystFEL tools in your `PATH`.
 ### Homebrew
 
 To install the development version of CrystFEL using
-<a href="https://brew.sh/">Homebrew</a>, run the following:
+[Homebrew](https://brew.sh/), download the latest version of
+[crystfel.rb](https://gitlab.desy.de/thomas.white/crystfel/-/blob/master/crystfel.rb)
+from the Git repository, and use `brew install`:
 ```
-$ git clone https://gitlab.desy.de/thomas.white/crystfel.git
-$ cd crystfel
+$ wget https://gitlab.desy.de/thomas.white/crystfel/-/blob/master/crystfel.rb
 $ brew install -v -s ./crystfel.rb --HEAD
 ```
+Omit `--HEAD` to install the latest stable version.
+
+Note that the Homebrew formulae included in the "tarball" release files always
+refer to the *previous* release.  This is because the formula has to contain
+the SHA256 hash of the downloaded tarball, which is not known until after the
+tarball has been created!
 
 We hope to contribute the Homebrew formula to the main repository soon, so that
 you can install CrystFEL with a simple `brew install crystfel`.