I know social media is the best place to promote and gain backlinks. Though I've done on facbook, youtube, pinterest, linkedin. But I've no idea how to go for instagram and twitter! Anyone here to suggest?
As you may be aware Instagram is the photo sharing media you can share your company photos in it & get traffic from there. Twitter is a bit similar to facebook, you can tweet posts with images or only text in it, use hashtags, tweet about company happenings & events also.
Just insert the link in your bio. It's a very effective way to promote backlinks. You can also insert them as captions on pictures but this is generally not recommended.
Forget building links with Instagram. You can have one link in your bio and if you have more than one account with the same domain IG is going to ban you. Unless you use a parasite domain like Facebook, Youtube, G+, etc…. Then you can post a slightly different video on youtube promoting the same offer and having another URL. But be careful, if you do spammy things like following hundreds of people daily and liking hundreds of posts your account needs to be at least 1 month old to put a URL in the Bio without risking a ban.