Introducing how does Boost work on Cash App. With Boost, you can quickly save money when using your cash card at coffee shops, restaurants, and other commercial establishments. To start, all you need is a Cash Card. If you already have a Cash Card, follow these steps to start saving: Touch the Money Card tab on your home screen Press Save with Boost. Touch a Boost. Touch, Add Boost. Start saving. You can visit our website for more detailed info.