2. The #1 factor for creating content that leads to sales
The #1 factor: Always be authentic
A lot of bloggers think that sharing the best features of an affiliate product and their enthusiasm for it is enough to make good affiliate sales. They might have been true 5 or 6 years ago, but as the number of ads our audience sees in a day has increased, our audiences have become even more sensitive to marketing messages.
I also see being authentic as a blogger as part of my calling. I have very few set in stone business policies, but one of them is that I only ever recommend products I've used and loved to my audience. If I recommend a product I haven't used, I'll say that super clearly.
For example, I get asked about website hosting a lot. I personally use Godaddy, and highly recommend them, but when I worked as a Wordpress virtual assistant I had a lot of clients who used WP Engine and loved them. I had a good experience with them when I dealt with them as a VA for my clients, but I never used them myself. So if I recommend them, I tell people that.
It's not about "having to disclose" or anything official I'm required to do, it's about maintaining my personal integrity and knowing my audience can always trust me to be honest with them. If your audience feels like you're just trying to share something so you can make a profit, then you're going to lose them and probably won't get the commissions.
More than any "tactic" authenticity is the biggest key to success in any business, especially affiliate marketing.