# Onboard using Mastercard Checkout Solutions Onboarding Application
source: https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/integrate_apis/step1/index.md

## Step 1. Onboard using Mastercard Checkout Solutions Onboarding Application {#step-1-onboard-using-mastercard-checkout-solutions-onboarding-application}

1. Order the [Mastercard Checkout Solutions - Sandbox](https://www.mastercardconnect.com/-/store-plus/item-details/A/srconbrmtf) on [Mastercard Connect](https://www.mastercardconnect.com/).

2. [Enroll in the programs](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/onboarding-sandbox/step4/index.md) you require for your sandbox projects.

3. [Create a sandbox project](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/onboarding-sandbox/step5/index.md). You can create up to 30 sandbox projects to allow testing in different lower environments.

4. Download the auto-generated [API Signing Key (OAuth key)](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/key-management/index.md) and [Consumer Key](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/key-management/index.md).

5. Download the auto-generated [Payload Encryption Key](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/key-management/index.md).

Note: For detailed steps on onboarding for each product in Mastercard Checkout Solutions, please refer to the [Onboard to Sandbox](https://developer.mastercard.com/mastercard-checkout-solutions/tutorial/onboarding-sandbox/index.md) tutorial.