A sandbox is a pretend version of Montonio. You can run test payments and no real money moves. You get sandbox keys as soon as you register – no contract needed.

## 1. Create the account

1. Open the [Montonio Partner System](https://partner.montonio.com/) and register.
2. Confirm your email and log in.

## 2. Copy your two keys

1. In the Partner System open **Home** from the left-hand menu. If you have more than one store, pick the right one.
2. Click **Get API Keys**.
3. Under **Sandbox API keys** copy the **Access key** and the **Secret key**.

If your business is already active and you added a new store, go to **Business settings → Stores**, click the store name, then **Go to API Keys**, and copy the keys under **Sandbox API keys**.

## 3. Paste the keys into your store

1. In your store admin open **Add-ons → Montonio**.
2. Open the **Test (sandbox)** tab.
3. Paste the **Access key** and the **Secret key**.
4. Click **Connect**.
5. Under **At checkout** turn on **Show Montonio at checkout**, plus the payment methods you want – **Show embedded BLIK for PLN carts** and **Show embedded card fields for PLN and EUR carts**.

Done. While your store is in [test mode](/help/getting-started/test-mode), checkout uses the Montonio sandbox.

## Good to know

- Your store checks the keys when you connect. If you pasted production keys into the test tab (or the other way round), it tells you and offers to save them in the right place.
- You do not need to set a notification address in Montonio. Your store sends it with every payment.
- BLIK works only for carts in PLN. Card payments work for PLN and EUR. Carts in other currencies fall back to your other payment methods.
- Refunds are issued in Montonio, not in YNS – see [Issue refunds and handle returns](/help/orders/refunds-and-returns).
- Before you start selling for real, open the **Production** tab, connect your live keys (in the Partner System they are under **Live API Keys**) and switch your store to live mode.