We're not suggesting you take the #SocMed equivalent of elocution lessons, but a little knowledge of some common social media courtesies wouldn't go amiss. The following suggestions are specific to businesses, not individual's personal accounts.
Be cautious with automated content
Scheduled and automated content can be a great tool for businesses - you can post messages to your followers at a time that suits them, which is more than likely outside of work hours. But, as will all things, there is a time and a place. In general, do not schedule a tweet which @mentions someone. If they reply instantly, they may be left hanging! It's the equivalent of calling someone, waiting until they say hello and then putting the phone down.
Another big 'no no' when it comes to online courtesies are automated DMs. We've all received them - "Hey (insert name)! Thanks for following it's great to connect!". Somehow this is both overly friendly and extremely impersonal. While people may be coming from a good place when they set these up, it's much better to just be more selective in who you thank for following and to be sincere when you do.
Don't spam your followers
People follow you on social media for a reason. It's good practice to know what the reason is and then stick to it. If you manufacture curtains then it's likely that your followers are interested in curtains. Don't digitally turn them off by incessantly tweeting about your cat. You may find it interesting but they probably won't.
(Actually, we'd suggest steering clear of incessantly tweeting about anything).
Be sparing with sales messages
Speaking of spamming your followers, the same applies when posting sales-type messages. These are absolutely fine to post about, but only in the right measure. No one wants to follow an advert.
Use correct grammar, spelling and punctuation
To the great relief of many, the internet has now ditched text speak in favour of correct grammar, punctuation and spelling. We can only assume that seeing as it served us so well for the past however-many-hundreds of years, that the internet didn't need to change that. So ditch the 'hey !! wat u doin l8tr???" for a simple "Hi! What are you up to later?". No one likes text speak any more. It's so 1995.
Always quality check your images
With a smart phone in almost everyone's pocket, everyone is a photographer and the standard for images on social media has rocketed. This means that you need to be very selective in which images you share online. Sharing poor quality image is like sharing a borderline-offensive joke at a dinner party - it makes everyone uncomfortable and ruins the mood. Don't let your social message be ruined by a blurred or grainy image.
Rise above negativity
It's not uncommon to experience some negative comments on social media. How to deal with complaints or negative comments is something to be considered by each business individually, and each negative comment should be dealt with separately. A few ground rules though are to avoid tit-for-tat bickering. This makes no one look good. Also, if you're unsure how to respond, rest assured that there is no urgency. Take an hour to calm down and go back to it later.