Do you have zero interest in an expensive mountain bike the company you are an affiliate of sells? Well, you probably don’t want to feature it on your blog, as it is extremely difficult to persuade readers (or anyone for that matter) that they should buy something you wouldn’t be caught spending a single penny on. When you are passionate about a product or–at the very least–interested in learning more about it, this will come through to your readers, engage them and better coax them to buy
The best way to find suitable brands to promote is by simply using a search engine using: '[Brand] + Affiliate Program'. Some companies run in-house affiliate programs however, this is a very specialist area. Therefore, most companies opt to employ an 'affiliate network' which has already built a large base of affiliates and gained years of experience in running successful programs for clients.
Know when to wait. Some affiliate programs require a certain level of traffic, subscribers, etc. If that’s the case, I say it’s better to wait to apply for that program instead of applying and hoping for the best. You risk being labelled the person who can’t follow guidelines and you might also risk not be allowed into the program when you do meet the qualifications.
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.