You will receive VIP points for each purchase of gold or gems. The more resources you buy - the more VIP points you will receive!
Each VIP level will give you a certain amount of resources each day. To reach the next VIP level you need to acquire a certain amount of VIP points that you can see on the progress bar. You can also check what the current and next VIP level will give you by clicking on the “i” icon:
If you’ll click on the blue “VIP” button, then you’ll be able to claim your daily reward.