Update README for info on creating bottles

README.md

@@ -17,3 +17,14 @@ For example:
 brew install maplibre-gl-native
 brew install maplibre-map-renderer
 ```
+
+# How to build bottles
+
+```
+brew install --build-bottle --verbose pointrlabs/vendor/formula-name
+brew bottle pointrlabs/vendor/formula-name
+```
+
+This will output the bottle stub that should be inserted into the formula. It will also produce the tar.gz archive, which you should upload into Releases section of the target repo. A couple more things to be careful about:
+- Before uploading, you may need to rename the archive to be like `maplibre-map-renderer-1.1.arm64_sequoia.bottle.tar.gz` (there are sometimes extra dashes, or unnecessary revision numbers, which should be removed).
+- You will need to update `root_url` to match the repo you are uploading the bottle to. This root url will contain the git tag as its last part with `%2F` as slashes (if your tag contains slashes). An example: `https://github.com/pointrlabs/maplibre-gl-native/releases/download/version%2Fmap-renderer%2F1.1`