How to avoid the promotional box with mailchimp?

Some of you may have seen a drop in open rates with MailChimp. It might be because of Google's inbox system putting you in the promotional inbox, might as well be put in the spam inbox off how much people care about the promotional one. Does anyone know how to bypass this? This is happening to me on the first e-mail I send my subscribers.

Granted, I haven't sent them an e-mail to confirm their subscription, i'll do that now and let yall know if it helped or not.