As title, what is your favorite? And what do you think is better to create a quality responsive list? I know there is nothing as the "best", but I really would like to know which traffic source is "better" to create a high quality list.
I'm not talking about "size" here, even getting 3 - 5 people a day is fine as long as the quality is real good.
Could any advanced list-building marketers shed some light please?
Perhaps there is something valuable or reports that I can refer to?
It will be very much appreciated.
Thank you in advance.