You will make an excellent passive income for as long as you want in this line of work. In fact, you will even make money on your old blog posts written years ago, depending on the quality and relevance of your content. Your business will always stay open, and you will have cash flowing into your bank account 24 hours a day, 7 days a week, even when you’re asleep or off on a vacation.
If your domain is your address, hosting is like the actual house within which your site will live. It's your own little slice of the internet — the place where all your website files live. Hosting is very affordable these days, so don't unnecessarily scrimp on costs. Go with a reputable, reliable provider because your affiliate marketing business depends on it. 
Petra- your keyword phrase “Beach Decor” can expect to get 374 hits per day for the number 1 spot on Google, but there are 189,000 websites in competition with you (hard to get to #1). But you can get to #1 easier with the keyword phrase “Sea Decorations” and if at #1 you can expect 50 hits/day and only competing with 12,600 other websites. Also “Beach Party Decorations”, #1 Google spot can expect 40 hits/day and competes with 16.200 other websites.
Thank you for the detailed article. For me personally is very inmportant the part that explains that is not a get rich quick scheme as many people expect tot get passive income in a week. You basically never start learning but how you said with the step just like building an email list you can get slowly there. How did you get into affiliate marketing for the first time?
Always disclose your affiliate relationship. Most visitors will probably understand that graphic ad will lead to your getting paid, but if you write a review or use an in-text link as a recommendation, you want your readers to know that may lead to compensation as well. This ensures you retain transparency and trust with your readers, but also, it's required by the FTC's endorsement rules.