That depends on the on your website, In case your website is small, if it is something that your making out of your interest or just to earn some extra income,then i suggest you do the marketing stuff yourself because it is not worth it to hire a professional to do the job, besides social media is one place where you can get huge amount of organic traffic to your site.The most effective among them is through the facebook groups. There are tonnes of FB groups which primarily focus on one topic,You will find groups created based one primary niche just like the bloggers do. All you have to do is just search and join the groups that have the same niche as your website and start posting in that group that's it done. But this is in case of a small websites, But if it is a big website then it is recommended that you hire some professionals to do the job as you can not just depend on social media marketing.