In order to apply the hook model to your product, first, you need to make sure that the stages of the model (trigger, action, variable rewards, and investment) are available in your product and can be followed by your customers. If one of the elements is missing, users will get out of the hook and won't stick to your product. Go through each of the 4 steps, and control your product sends triggers that draw users' attention, it is easy, and fun to use and allows users to earn achievements/rewards, which will motivate them to invest more in the product at the end.