I haven't signed the Indyref2 petition, I see it as pointless (and just like the anti ref2 one, horribly badly written) - But I have donated money to Scotref campaign- and so have a lot of people, over a third of a million pounds in 4 days. I would imagine that most people have pitched in small amounts, a pound, a fiver, a tenner. So that's a lot of people quietly donating a wee bit of their own cash.
Also, after the bitterness of the last 2 referenda (Indy and Brexit), I'm circumspect about sharing things on fb (a few likes and shares of favourable articles mainstream articles but no shares of anything inflammatory ). My extended family (No, Brexit, UKIP and Tory voting) have been sharing the most vile memes, ad hominem attacks on NS, and a lot of angry, nasty stuff. This time I'm choosing not to engage (or compete), with that... they won't be won over, but they might alienate a few "maybes" by their behaviour.
It might be a mistake to think that those making the most noise reflect the majority opinion (they might, we won't know until the actual vote) 