First of all join InstaFreebie: https://instafreebie.com?invite_code=acE1gC9YIa
It’s a site where you set up your book for download via email. People get a mobi, epub, or pdf sent to them in exchange for their email. This is great for writers and readers of all kinds.
The second thing you do it go to Pricing and click the Plus Plan. You get 30 days free from Instafreebie to try it out so it’s entirely worth it. With the Plus plan (it’s $20 a month after the first month) you can make it mandatory to join your mailing list in exchange for a book (as opposed to there being a little check to opt-in, and we all know no one ever clicks the little check when signing up for things). I was a little hesitant about this at first, but well, they can always unsubscribe later on if they just wanted the book (mention this in your newsletter! Some folk will mark as spam no matter what though).
Third: Use Facebook. Yes, I’m serious. There are a ton of facebook groups and pages for authors working together to exchange newsletters, promos, and to help each other out.
There’s InstaFreebie Promos: https://www.facebook.com/groups/instafreebiepromos/?ref=br_rs
FreebieFriday on Instafreebie: https://www.facebook.com/groups/578910405624973/?ref=br_rs
InstaFreebie Push: https://www.facebook.com/groups/674062869429630/?ref=br_rs
InstaFreebie Share Group: https://www.facebook.com/groups/instafreebiebooksharegroup/?ref=br_rs
And there are also groups devoted to specific genres.
Then join as many promos as you are qualified to join. Some are free, for others you may need to pay in, many are divided by genre. These are mostly everyone-pitches-in promos, so all those that joined in all spread the word to their newsletter/mailing list/blog/social media.
You can also join Newsletter Swap: http://newsletterswap.com/ and set up your book there, asking others to send your book out to their people (if you’re still growing your list, it isn’t mandatory to actually swap). It lets you put in any store link you want, including Instafreebie.
You’ll collect the emails on InstaFreebie (unless you use Mailchimp, integration with MC is also part of the $20 plan). You can download them as a CSV. They’re broken up into Subscribers and Unverified (need to download them as separate CSV files), the latter being that IF couldn’t send them your book. I put both into my list and find that most of the ‘unverified emails’ do work.
(The Pro plan at $50 a month isn’t worth it, imo. You get to use more pen-names, and change the color of the ‘Claim’ button).
Doing this I went from 26 subscribers in December to almost 3000 today. I have about a1/3rd open rate, and I’ve grown a team of 50 ARC and beta readers
(Oh, and if you want to join my mailing list, pop over to this page and grab a copy of Larkspur! https://vmjaskiernia.com/newsletter-and-free-books/ )
Happy list building!