Best practices to build pre-launch email list for dirt cheap. Advice needed.

I am building my pre-launch email list - to which I will advertise, once my product goes live.

So far, I am sitting at around 250 people according to MailChimp.
I'd like to build it up to at least 1000 before launch.

My strategy is as follows:

1) drive traffic to the landing page (FB ads = 6% CTR, 0.08 c per click);
2) visitor signs up (12% conversion);
3) the user gets forwarded to the "thank you" contest page, where they are encouraged to share the product page with their friends (or...

Best practices to build pre-launch email list for dirt cheap. Advice needed.

from Best practices to build pre-launch email list for dirt cheap. Advice needed.