A lot of bloggers put together a blog without any real plan for how they're going to promote it or monetize it. Putting a blog together without a plan is like trying to build a house without a blueprint.
It's possible, yes. But the end result is probably going to be shoddy, and the whole thing could fall apart at any minute.
You should create a solid plan of action before you even buy the domain. You need to develop a strong blueprint before you ever get started. Waiting until after you've already set it up and are getting traffic could mean a lot of extra work going in to correct mistakes.
Changing themes and adding plugins after you're already getting traffic could interrupt your traffic. Sometimes new plugins and themes can temporarily break your blog, which could mean a loss of traffic (and money) until you're able to fix everything.
The first part of your plan should be choosing a niche, of course. Part of choosing a niche is finding products you can promote. If a niche has no products available, you could create your own.
But if there are no affiliate products available, it could be because there isn't enough demand there for a product. In this case, you'd have to do some careful market research in order to determine whether or not a niche is truly viable.
What's your purpose for blogging?
Do you have your own product you want to promote?
Do you want to promote affiliate products?
Do you want to just put AdSense or CPA offers on your site?
You need to ask yourself questions like these so that you'll know how you intend to monetize the site. If you plan to promote affiliate products, you should test the products yourself before you promote them.
If you don't, your visitors could end up being very upset if you promoted a product of really poor quality and they bought it because they trusted you. Even worse, what if you end up promoting something that turns out to be a scam?
You don't necessarily have to purchase every product you wish to promote. If you can prove you have a decent amount of traffic (and sometimes if you just ask), you may be able to get free review copies of some of the products you'd like to promote.
It doesn't hurt to ask. Even if you don't have any existing traffic yet, you can write to the owner of a particular affiliate program, tell them what you're planning to do, and ask if you could get a review copy.
Some people won't give you a review copy. Plenty of marketers get requests for review copies from those who just want to get a copy of their product for free. So if you run into a skeptic, or someone who's been burned before, you may get turned down.
In this case, it's probably best to just go ahead and buy the product if you really want to promote it. If it's a scam or a really crappy product, just ask for a refund.
You can also consider using a donation button on your blog. If you can't find any good products to promote, and you don't have the time, money, or ability to create your own product, you can still put up a donation button. If your blog is very good, you may get donations.
Or, you can always sell ad space on your blog. If you start getting a substantial amount of traffic or you get a very high PageRank in Google, you could charge a lot of money for a link on your blog. You can also get paid for making posts on your blog that review other sites.
