To boost a post on Facebook, you really have two options. One, if you already have a post that you would like to boost, go ahead and click the blue button. As you scroll down, you’ll notice it on all the posts throughout your page. The other one is going to be on a new post. If you’re gonna add a new post, you’ll see the white button here that says, “Boost post.” Now, I do recommend doing some additional research. Facebook has a great page, which I’ve linked, that kind of goes through all the different elements that you should consider.
Whether or not are you going to post to people who like your page, that like your page plus your friends. Or are you going to actually trying to target people outside of your Facebook page. The other nice thing is you can budget as little or as much as you’d like. I don’t recommend going below $5 though. Once you’ve selected your target audience, Facebook will actually give you an estimate of the number of people that you’ll reach. Once you’re set, select the number of days that you’re going to boost for depending on your dollar amount, and then click “Set budget” and your ad will have to be approved by Facebook before it goes completely live.