On your phone, open up your app's menu. Scroll down and find the Safaricom Toolkit
Open the Safaricom toolkit and select MPesa.
Look for the second last option called "Lipa an M-Pesa" and select it.
Three more options will open up, select the first one called "Pay Bill".
Choose "Enter Bussiness number". Here, key in the Betika Paybill Number, 290290. Press OK
You will then be asked for your account number. Enter your account number and select ok
Enter the amount you would like to deposit to your Betika account.
Lastly, enter your MPesa pin. Remember that this is your secret; don't show it to anyone else.
Done!!!