If you'd like to withdraw money from your cash balance, just follow these steps:
1. Go to your Portfolio and tap the cash balance banner
2. In the cash balance screen, tap the "Payout" button
3. Enter the amount you'd like to withdraw. You can withdraw up to the "available for payout" amount stated on the screen
4. Confirm your payout.
That's it! The money will be credited to your verified bank account within a few working days.