You could do it yourself but...
I've heard it before, I think everyone has "We have that data" or "We'll just hire X freelancer to do it".
It's easy to outsource your content from graphic design, to photography and videography... I've done it. Just be aware, it is a huge time commitment, and it can cost a lot of money if you get it wrong, or worst still, it could damage your business's reputation.
Here are some simple steps to do it yourself: First jump on a website like The Right Fit or if you're super tight on funds Fiverr or 99Designs, put your criteria in, pick one, and off you go. You'll often get the content you need, but first you'll need to sort through the applications you get, then you'll need to make sure you've budgeted for the sort of content you need correctly (often what you think is required to get certain sorts of content and what is are very separate, be prepared to negotiate and ask questions). You'll need to make sure they're local, and can actually do the work.
Just remember with these websites, they're not there to make judgement calls for you, or help you get your content, they want to do it as quickly and as lean as possible. For freelancers on many of these websites it's a volume game (they need lots of clients, to break-even/make money).
If you haven't already you'll need to look at how the content fits with your overall strategy and then you'll need to write a brief. Then you will need to be there when they execute it, after that, you'll need to provide feedback on the edited content, and make sure it communicates to your audience, then you'll need to figure out where it should go, how it would best engage with your audience, and then post it, at the right time, in the right place, with the right context.
Now, most people think that social content ends here, but if you only do it once a month, people WILL forget about you, your product, services and the value you're offering them.
How many hours do you think it takes to build up this relationship with freelancers? You'll need to make sure they've got the time, and when they don't post the brief and find another. Then check your metrics, make sure your strategy is converting, and you are continually engaging with your audience.
It's not one strike, one fit, wonder, campaigns and campaign budgets are annual, and how you spend them, and how you continue to grow. You could do all of this, most people hire a marketing manager, or have a marketing team, but often online content is only a small part of the battle, marketing is a broad range of skills that help your business maintain and grow their client base; It's everything from the price, to your product, how you promote it, and where it is placed both physically and in the minds of your audience.
I'm not saying this to discourage you, and you could do it yourself but... Sometimes it's best to hire an expert.
If you want to talk more, you can email me here.