• Open the Google Play Store app
• Tap Menu > Account > Add payment method
• Follow the onscreen instructions
• The new payment method will be added to your Google account

For more information about available payment options, you can also take a look at this Help Center article.

​Edit a payment method

 

• Open the game
• Select the Offers tab
• Choose the package you want to purchase
•  Tap on the selected card or on ""Payment methods""
• Choose from one of your existing payment methods or add a new one
• Complete your purchase

Note: if you add a payment method while making a purchase, it will be saved in your account.

​Remove a payment method

• Open the Google Play Store app
• Tap Menu > Payment Methods
• Select the payment method you would like to remove
• Tap the 'More' button in the top right, and select ""Remove Payment Method""

The payment method will be removed from your Google account.

Accepted Payment Methods on Android
Google Play processes all purchases made via the in-game Offers tab. Google purchase methods vary by country.

Credit & debit cards: Visa, MasterCard, Amex, additional country-specific cards
Carrier Billing: depending on customer country and carrier (complete list to review here)
Google Play gift cards: available in selected countries (complete list to review here)
Google Wallet Balance: only available in the US and UK
If it's your first time making a purchase, your payment method will be added to your Google account.

For a list of available methods by country, please visit this link.