Update README.md (#47)

Extended local setup instructions

attribution-reporting/README.md

@@ -2,13 +2,19 @@
 
 ## >> [Live demo](https://goo.gle/attribution-reporting-demo)
 
-## Set and run locally
+## Set up and run locally
 
-1. Run `git clone https://github.com/GoogleChromeLabs/trust-safety-demo.git && cd trust-safety-demo/attribution-reporting`
-1. Make sure you have [node.js](https://nodejs.org/en/download/) and the latest Firebase CLI `npm install -g firebase-tools` installed.
-1. Install all dependencies in the functions folder `cd functions && npm install && cd ..`.
-1. Run the Firebase emulator with `firebase emulators:start` to startup all the sites. If you have no Firebase project setup you can add `--project none`.
-    * Make sure you see the following output and port mappings. If the port mappings differ please see the [#Troubleshooting](#troubleshooting) section.
+### Set up (one time only)
+1. If it's not yet installed on your machine, install [node.js](https://nodejs.org/en/download/). 
+2. Install the latest Firebase CLI by running the following in your terminal: `npm install -g firebase-tools`.
+3. In your terminal, run `git clone https://github.com/GoogleChromeLabs/trust-safety-demo.git && cd trust-safety-demo/attribution-reporting`. This command will create a folder, clone all of the `trust-safety` demo code in that folder, and navigate you to the `attribution-reporting` demo subfolder.
+4. In your terminal, run `cd functions && npm install && cd ..`. This command will install all the required dependencies for you to locally run the `attribution-reporting` demo.
+
+### Run locally
+1. Optionally, pull the latest code from this repository: in your terminal, navigate to `trust-safety-demo/attribution-reporting` and run the `git pull` command.
+2. Locally start the demo: in your terminal, navigate to `trust-safety-demo/attribution-reporting` and run `firebase emulators:start`. If you have no Firebase project setup you can add `--project none` (`firebase emulators:start --project none`).
+    * You should now have multiple servers running: home(:8080), adtech(:8085), advertiser(:8086), publisher(:8087) server.
+    * Make sure you see the following output and port mappings in your terminal. If the port mappings differ, see the [#Troubleshooting](#troubleshooting) section.
 
     ```sh
     ...
@@ -23,9 +29,8 @@
     ...
     ```
 
-1. You now have multiple servers running: home(:8080), adtech(:8085), advertiser(:8086), publisher(:8087) server.
-1. Open [arapi-home.localhost:8080](http://arapi-home.localhost:8080) in Chrome.
-1. Follow the instructions in the UI. 🚨 In particular, make sure to follow the **Set up your browser** instructions.
+4. Open [arapi-home.localhost:8080](http://arapi-home.localhost:8080) in Chrome.
+5. Follow the instructions in the UI. 🚨 In particular, make sure to follow the **Set up your browser** instructions.
 
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