These are extremely crucial to any social media strategy, specifically, because most people try to do one or two of them but do not get all of them right. It's also because most of the people learning social media on their own are not getting educated in the depth of Social Media.
The first 'P' of Social Media is Platform. A lot of the people have the same strategy for Facebook and Instagram that over arches across other platforms, it doesn't work like that! People don't use Instagram to do the same things they do on Facebook, similarly, people don't use Twitter to do the same thing they do on Instagram. Every platform must be respected for what it does. We need to understand what kind of audiences each platform has, the content consumption behavior, the demographics and only then will you be able to tell what the audiences want to engage with.
Secondly, it's about People. The entire concept of a social network is to allow people to connect with other people. No person logs in to Facebook to talk to a brand; some people still use Twitter as a customer care service but most people don't go to these platforms to engage and interact with brands. Therefore, it is crucial for marketers to humanize their brands!
For example, let's treat every social media party as a cocktail party. Now that a brand has made its way to the cocktail party, it can't act like a sales person because no one is really looking to buy! The brand can though go around talking to people, having real conversations; understanding if the brand can add any value to the others. If it can't, then it's not necessary to behave like an 18-year-old and try to close on the first night. The brand should focus on a longer relation. In case it can't add value to some there's nothing wrong in having a nice conversation with people. Who knows they may recommend you to others without you even realizing it. That is a basic word of mouth marketing and social media simply puts it on steroids.
Then you have the Paid Activities. It's extremely important for Social Media strategy to have paid activities. Every time you need to reach to your customers, you should want to be able to use those paid tools as per the situation. All these platforms have a massive amount of data on their users and being able to contextually reach them based on their recent activities is invaluable. The key lies in using these tools over and over so that you understand what targeting and creatives work for you to ensure you the best bang for your buck!
The fourth and probably the most important aspect is Performance Benchmarking. You have to keep going back to the analytics. Understand that digital media is the only kind of marketing platform that gives you detailed data on every aspect of everything you do on social media.
For example, if someone visits my website, I can tell what's their age, which phone did they use, what time did they come, what kind of internet connection they had, which pages they visited, how did they navigate the website, etc.
So keep a track of what is working for you then put your two cents in and get a dollar back!