1. First you need to add money to your Mode Sterling account. You can find a step-by-step guide here
  2. After you've credited money to your Mode GBP account tap the down arrow again
  3. Tap BTC
  4. Tap the icon to the left of your balance
  5.  Tap "Buy" 
  6. Enter the amount of Sterling you want to exchange for Bitcoin
  7. Review your order and press "Confirm & Buy"

Please note that the price of Bitcoin varies from moment to moment so you may notice that your Bitcoin has decreased or increased in value when it is credited to your account, however you will always receive the exact amount of Bitcoin advertised.