Step #1: Preparation
Find a product related to your niche and write a review on it. It doesn’t have to be all positive, sometimes people are more willing to trust you when you tell them what you don’t like about the product.
Add your own bonuses to spice up the offer, it can be some PLR products or services that are of value to the main product.
Step #2: Send Traffic
You need to choose at least 1 or 2 traffic sources to let people read about your review. Basically there are free and paid methods, but I would suggest using both.
Free methods: Facebook friends, Youtube subscribers, Instagram followers, Blog readers and Email leads.
Paid methods: Facebook ads, Google adwords, Bing ads and Solo ads.
Step #3: Tracking and Testing
If you are using more than one traffic methods, you need to know where the audience are coming from, what action have they taken and what is the Cost Per Action (CPA)?
Therefore you would need to have your link setup so that it can be tracked, and make changes accordingly to boost up your conversion rate, also known as split testing.
I believe once you have all the steps in place, you business will definitely improve over time.