some tips

Author: metamaskbot

packages/foundryup/README.md

@@ -10,6 +10,38 @@ or
 
 `npm install @metamask/foundryup`
 
+## Usage
+
+Once installed into a package you can do `yarn bin mm-foundryup`.
+
+This will install the latest version of Foundry things by default.
+
+Try `yarn bin mm-foundryup --help` for more options.
+
+Once you have the binaries installed, you have to figure out how to get to them.
+
+Probably best to just add each as a `package.json` script:
+
+```json
+"scripts": {
+  "anvil": "node_modules/.bin/anvil",
+}
+```
+
+Kind of weird, but it seems to work okay. You can probably use `npx anvil` in place of `node_modules/.bin/anvil`, but
+getting it to work in all scenarios (cross platform and in CI) wasn't straightforward. `yarn bin anvil` doesn't work
+in yarn v4 because it isn't a bin of `@metamask/foundryup`, so yarn pretends it doesn't exist.
+
+This all needs to work.
+
+---
+
+You can try it here in the monorepo by running `yarn workspace @metamask/foundryup anvil`.
+
+
+
 ## Contributing
 
 This package is part of a monorepo. Instructions for contributing can be found in the [monorepo README](https://github.com/MetaMask/core#readme).
+
+