How do you know how often you should post content on social media? There are no rules, so you'll have to test it or figure it out somehow. The easiest way to test it is to check our own reaction. Others' reactions and opinions take a bit more work to be sure they're representative of your true intended market, but what others think can be much more valuable than your own feedback in a mirror.
So if you want to start easy and get your own opinion, for goodness' sake don't actually look at your own updates and tweets. Check out other folks. Your reaction to their level of activity is a great gauge of what your market thinks about your own content. Make sense?
Let's break it down.
Do you have a sense of how much is too much? For you, personally, is there a point when someone else's posts, Tweets, or updates get just too annoying or bothersome because they're just always there? Does the information seem repetitive, meaningless, and not even entertaining? Just plain irritating? When you identify a similar person or business on social media whose content frequency bothers you, well chances are, assuming you're a good representative of your target market, that's a way to figure out the upper limit. So back off from that much.
Of course it'll also help to have a sense of the lower limit, the minimum required to actually get someone's attention and stay top-of-mind. Fortunately most social media sites make finding the lower limit easy, just pick a few folks you feel have the right amount of presence and then look at their content flow for a few days and check the average.
Oh yeah, and how do you know how often is too little? Well, you don't really, because those are the folks you're not even aware of since they're not on social media at all or so seldom they might as well be no-shows.
You can use feedback from your target market, either formally sought after feedback or just anecdotal feedback, to check out what others think of your posting frequency. One suggestion is to identify a dozen or so ideal target market folks and check in with them, stressing that you're looking for helpful feedback, not just a pat on the back. Honest feedback is extremely valuable. You can set up a formal process or keep it loose, but the closer you pay attention to others' feedback (again, assuming the feedback comes from your true market, not someone off the mark who wants to rage or praise about your content but whose feedback is irrelevant to your business purpose).
So, look inside to check your own gut reaction to posting frequency. Then survey your market. The point is to be there (on social media) enough to be noticed favorably but not so much you chase your market away. Once a second is likely too much and once a day is not enough - so somewhere in the middle is right - but what's right for you or your business is up to you to find out.