1. Obtain the Clash v2ray subscription URL that you want to use.

2. Download and install a Clash client app such as Kitsunebi or Clash for Android.

3. Open the app and navigate to the subscriptions settings.

4. Find the option to add a new subscription.

5. Enter the Clash v2ray subscription URL in the appropriate field.

6. Save the subscription and select it for use.

The specific steps may differ slightly depending on the app you are using, but the general idea is to add the subscription URL to the app and then select it for use. Once the subscription is set up, you should be able to use the Clash v2ray proxy service on your Android device.