This is how you buy Bitcoin with cash app create a cash app account download the application and create an account set up a username and password link your cash app account to your checking or savings account once your bank account is linked to the app you'll be able toMake purchases go to the buy Bitcoin screen to purchase Bitcoin tap USD on the cash app home screen a menu will pop up at the bottom select the option buy Bitcoin add purchase details and finalize enter the dollar amount you'd like to purchase then enter your PIN and confirm the transaction