Once digital banking is added, and you've added the breakdown of the funds. You will be prompted to complete the Source of Wealth screen.
In here you get to explain in a bit more detail how the funds were obtained.
 Step 1: Tap on confirm my source of wealth. |  Step 2: tap on begin. |  Step 3: You can use the template provided as a guide on how to complete SOW for each of your SOFs |
Remember to provide this for all declared funds.