High up
NN/g recommends prioritizing them over more generic recommendations. Put that ‘Recommended For You’ section high up on the homepage. (source)
Tell them how
Specify how you came up with those personalized recommendations. They can be based on their previous orders and interests.
At a minimum, mention that these recommendations are ‘Based on Your Past History’ or ‘Related to Items You’ve Purchased’.
A good example is Netflix:
Amazon
Categories
Break down the personalized recommendations in categories, especially if you have a large inventory. For example, Spotify groups their recommendations by music genre.
Fine-tuning recommendations
Provide users with a way to fine-tune the suggestions
This can be for example a Like or Dislike action. A long while back, I was using Pandora, when it was available in Canada. From what I remember, I could give feedback as to which songs I liked, so that it could suggest more of that style.
On Amazon, you can open your browsing history and give feedback on the recommendations, by clicking ‘More Like This’ or ‘Remove’ (image 3)
As soon as the feedback is provided, the recommendation list should update immediately.