Different recommendation strategies can be implemented for specific pages. Here are the best ones.
Homepage. Since the homepage is the main point of entry for your new visitors, the 'Most Popular Products' block featuring best-selling products would be the best strategy. When a new visitor comes to your store, you don't know what products to recommend. Showing other people's social proof on the main pages is the first touchpoint with the lead for further engagement.
Category page. One of the surest ways to help visitors on category pages find what they're looking for is to display them what most people are looking for. So the 'Most Popular Products' is a great strategy to use here as well.
Product detail page. The 'Similar Products' and the 'Customers Who Bought This Product Also Bought' blocks are traditional options for product detail pages. However, if you need a more flexible option, consider the 'Products by Attribute' block. For example, you sell daily planners and you want your customers to buy pens along with your planners. So, you can create the 'Products by Attribute' block based on product tag the planners and pens share and name it, say, 'Pairs perfectly with'.
Shopping cart page. The 'Customers Who Bought This Product Also Bought' block is the perfect option for cart pages. It encourages users to make quick buying decisions, often resulting in upsells.