Update README.md

Author: devpato

README.md

@@ -18,24 +18,31 @@
 </div>
 
 # PayPal JavaScript FullStack 3Ds Advanced Checkout
-This sample app shows you how to build and customize a card payment form to accept debit and credit cards and using 3Ds for authentification. Style the card form so that it aligns with your business branding.
+This sample app shows you how to build and customize a card payment form to accept debit and credit cards and use 3Ds for authentification. Please make sure to style the card form so that it aligns with your business branding.
 
 To create this application from scratch, follow the [Advanced Checkout integration](https://developer.paypal.com/docs/checkout/advanced/integrate) guide from the [PayPal Developer](https://developer.paypal.com/home) docs.
 
-### Run this App
+## Run this project
 
-You can run this app locally or on [Stackblitz](https://stackblitz.com/edit/pp-so?file=README.md).
+### PayPal Codespaces
+[![Open Code In GitHub Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/paypaldev/PayPal-JavaScript-FullStack-3Ds-Advanced-Checkout-Sample?devcontainer_path=.devcontainer%2Fdevcontainer.json)
 
-#### Run it locally
-You will need to create a `.env` file with the following environment variables:
+- Rename the ``.env.example`` file to `.env`.
+- Add your environment variables in the `.env` file.
+```shell
+PAYPAL_CLIENT_ID=YOUR_CLIENT_ID
+PAYPAL_
+
+### Locally
+
+- Rename the `.env.example` file to `.env`.
+- Add your environment variables in the `.env` file.
 
 ```shell
-CLIENT_ID=
-APP_SECRET=
+PAYPAL_CLIENT_ID=YOUR_CLIENT_ID
+PAYPAL_CLIENT_SECRET=YOUR_APP_SECRET
 ```
 
-In the `checkout.ejs` replace the `YOUR_CLIENT_ID` string in the  `script` tag with your PayPal Client ID.
-
 Complete the steps in [Get started](https://developer.paypal.com/api/rest/) to get the following sandbox account information from the Developer Dashboard:
 - Sandbox client ID and the secret of [a REST app](https://www.paypal.com/signin?returnUri=https%3A%2F%2Fdeveloper.paypal.com%2Fdeveloper%2Fapplications&_ga=1.252581760.841672670.1664266268).
 - Access token to use the PayPal REST API server.