Be your own client
Sell what you love and it stops being a job. Choose products that you believe in and try them out in advance (if feasible.) If you come across a product you know nothing about but it fits your profile, learn as much as you can about it. Read about the product, use it, become familiar with it. Of course, you might not feel passionate about every product, but great product knowledge will help fill that gap.
Fits within your niche
This may seem obvious, but it’s such an important point worth stressing. Finding products that are related to your blog is essential to success. You can, however, think out of the box and be creative. For example, if you’re writing a travel blog, you do not have to limit yourself to just the destinations you’ve visited, but you can add more tips on cheaper flights (Skyscanner), travel insurance (Axa), 4camping, You are using a camera, mobile (Mall) technology. Just everything related.
More brands from one category
If you are writing about one category, you recommend a particular product to your audience. You do not need to limit yourself to just one advertiser / e-shop. Take a look at the direct competition of the e-shop you already promote if they do not have the same or similar products that would fit your focus. The affiliate marketing principle is to connect you with as many brands as possible.
Desired by your target audience
Following on from the first point, whatever affiliate programs you promote must be desired by your target audience. The first step is understanding exactly who your target audience is. Hopefully you have already actioned this before you started your blog, but it is worth revisiting to clarify this point.
There are several ways to do this, but it starts by creating a customer profile. Be very specific here and make the person you are selling to as real as possible. If you have a customer base already, use this to determine who is currently buying your products.
Quality product and brand
The product must be good. Making your customers happy is the best way to long-term success, and quality products are a large part of that equation. Over time, you will earn a good reputation that will go a long way to aiding you in your future sales. The most important criterion for product selection is your own passion. People give a lot of emotions. Your reader will know if you like the product or not.