When promoting affiliate offers, just make sure you are fully aware of all the terms and conditions attached to your affiliate program. Some programs can be strict about how they allow you to promote their products. For example, some may limit you to banner ads and links only, while others will allow you to use paid advertising, but won't allow email marketing.
If you are interested in learning the process behind building a WordPress website then you should look at Learn how to Build High Quality Affiliate Websites. This will help you not just learn how to promote but also get you going with setting up the wordpress website and then promote relevant products. Andrew’s course is a Bestselling Course and we have no doubts why. The following pointers should help you make up your mind. Think of this program like going to affiliate marketing school.
If the answer to each of these questions is a resounding yes, rather than jumping to conclusions immediately, take time to research whether or not others are out there making a sustainable affiliate income from products and content in this niche. In a sense, competition is a good thing here—it'll help you validate your idea and prove that it's worth of building a business around.