Considering that you have a finite amount of time, passive income should make up a large part of your work. If you're serious about generating any semblance of income online, then passive income should be one of your sole goals and ambitions. Why? Wouldn't you prefer to do the work one time and get paid repeatedly as opposed to relying on your time to generate that income? Invest the time at the front-end so that you can reap the benefits on the back-end. This means putting in a bit of sweat equity and not getting paid today. Rather, you'll get paid somewhere down the road. And you'll continue getting paid whether you keep building that passive income stream or you stop. 
I have found that one size doesn’t fit all. Rather, specific types promotions of particular products work well with Amazon. I have also had some success by getting people in the Amazon door for other reasons. For example I’ve experimented a couple of times on dPS with running a posts that gave readers a hypothetical $1000 to spend on photography gear and asked them to surf around Amazon and choose what they wanted to buy. The result was 350 comments (a fun community building exercise) and quite a few sales and commissions!

Consider selling in lots. A lot is a collection of similar items that is sold in a group. For example, if you have a collection of books, magazines or similar pieces of jewelry, consider selling them all at once in a lot. You many not make as much money as you would have if you sold each item separately. However, the items will likely sell more quickly in a lot than they would individually.[29] 

As search engines have become more prominent, some affiliate marketers have shifted from sending e-mail spam to creating automatically generated web pages that often contain product data feeds provided by merchants. The goal of such web pages is to manipulate the relevancy or prominence of resources indexed by a search engine, also known as spamdexing. Each page can be targeted to a different niche market through the use of specific keywords, with the result being a skewed form of search engine optimization.