On your task bar you will see a safe icon.
If you click on the safe icon, it will give you a list of choices. Most of the choices will be to purchase credits.
The last choice in the list is to earn credits.
Click the last choice & a new screen will pop up.
On the new screen will be choices for different ways to earn credits.
After you have completed a choice for earning credits, click "Return to CafeMom" and the screen will close.
When you get back to your farm, there will be a screen to complete your transaction.
If you watched a video, your credits will usually show up right away, but if you did a task, then it may take a few days for your credits to show up.
Earned credits are listed at the top of the Farmandia screen where it says "credits".