Hiii, you messaged me on the fanfic message board about interaction etiquette, but the fanfic profile doesn't allow self promotion or some thing like that
I don't even know what cold messaging is lol ಠ_ʖಠ... But I don't think your message was one at least...
Well, you could just find an account, usually I go to accounts that I think will be interested in my contact, check them out, then message them saying "Hii, I think your profile is cool..."
Then you can add a reference to something they said like for example if the profile says "leave a hi if you read to the end of this bio" you can say "also I read to the end of your bio, so HIII... again... Follow for follow?"
Or if you don't want to say follow for follow you can say "Wanna follow and explore each other's reading lists?"
Most of the people that answer will say yes... And then you can also leave a random hi every now and then and ask how their day is doing... That way you form bonds and whenever you publish a story, they are more likely to check it out, because they know you.
They'll also check your account for things they might like, especially if you are into the same things.
And it's kind of nice talking to people on Wattpad. They are nice most of the time. Especially if you're nice first.