It all depends on your type of business. No singular marketing plan for social media platforms will work for all types of businesses. Consulting services is a little too vague... what niche do you focus on? Most consultants work in the B2B (business-to-business) realm, so focusing your efforts on LinkedIn may provide a better ROI than Facebook, for example.
What you need to do is develop your buyer persona and understand which platforms your target audiences frequent and how to best reach them via targeting options. Organic reach continues to decline, so you'll need to be ready to invest in paid media to reach a larger audience and generate leads. Once again, I prefer LinkedIn to other platforms in this regard because of its ability to fine-tune targeting based on job titles, job functions, a company's size, a company's industry, etc. Facebook does have similar targeting, but more of it is being retired after the issues with data being sold recently.
As a consultant, you have to exhibit yourself as an authority in your niche. One way of doing this on the organic side is to create content and distribute it via blogs, social media networks, industry-specific websites (such as Business.com, for example), etc. The more valuable and authoritative content you create, the easier it will be to gain influence within certain circles and build a following.
If you could get into more detail about the type of segment you focus on, I can provide more industry-specific ideas of what to do on social.
The very first thing you need to do is to find the right platform for promotion. Spot the social media platform that is popular among your customer base. Refer this article: https://www.knowband.com/blog/ecommerce-blog/know-social-media-site-popular-among-target-audience/
Once you have figured out the platforms that you need to target, start by doing some competitor's research. See the kind of contents that they are posting. Check out the posts that are engaging more users and getting more hits and comments. Create such contents for your account as well.
Keep posting on regular basis. Engage the users. Respond to their comment even if it's negative. Go for moving pictures instead of still once. Create interesting videos and posting them on your social media account can help as well.
Social Media Promotion is on the rise since all sorts of social media platforms are driving loads of traffic. It seems easy but it is not. The first and the most basic thing you should be doing is researching to understand what does your target audience look like, and what social media platform do they use. Try to understand that then go ahead with your promotion on that particular platform.
By creating content around your business and molding it according to the context of the platform and then distributing it to the targeted audience. Remember, posting the same content on all the platforms will not work. People behave differently on each platform.