Pretty ambivalent about social media. I'm sure it can be a useful tool and I wouldn't discourage anyone from developing that skill set, but it just isn't all that necessary if you are good at cold approach. One, if a girl likes you then that'll color all her perceptions of you--Oh, he never posts. That must mean he's out doing cool stuff. Two, I don't even give girls my real name until I've had long enough to see what they're about; definitely don't want potentially malevolent randos having that much access to my personal life. Three, if I'm doing cool stuff the last thing I want to do is stop what I'm doing and film it. Four, IME the highest quality girls, or at least the kind I most enjoy spending time with, aren't super involved in social media. Five, most of the girls I've slept with aren't and never were on any my SM; most of the girls I've added on SM I've never slept with.
That could be that my internet presence just sucks, but more likely SM gives them enough 'security' that they have me on their roster or locked down as a potential source of validation and makes sleeping with me less urgent.
Also, here is where frame comes into play. Do you like social media? Would you post sh1t if perceived potential pvssy wasn't on the table. If so, go for it--that's a perfectly legitimate frame. If not, don't. Do what's congruent to you. Personally, I'm more of the aloof, mysterious type--that's a natural part of my personality and so my game is tailored to that and I can make it work for me. If you're more of a friendly, social type, then adding someone on IG and inviting them to a social event would be congruent to that.
That said, in 2018 if you're dealing with late teen, early 20's girls, then you need to be on Snapchat. It has a super ephemeral quality that helps girls let their guards down due to perceived anonymity & if she has a BF it is by far the preferred means of communication--no paper trails. Personally, I always get the # and she'll let me know (usually some bullsh1t excuse about switching phone companies or w/e) if I need to use that avenue.