Hello @pacificcookiecompany,
Welcome to the Klaviyo Community and to the Klaviyo platform!
Some common mistakes I see often that would impact one’s deliverability when migrating platforms are:
In my experience, I hear a lot of brands wanting to explore an email marketing platform before fully committing or doing a slow transition while still sending on their old/previous email platform. This is actually ill advised.
By using two different providers, it makes it difficult for inbox provider to determine which source you’re actually sending emails from versus a potential malicious actor - even if both sources were legitimate. Because of this, it’s best to fully commit to the migration.
Being too hasty on the new platform though would also be a detriment and impact deliverability if you haven’t gone through a warming process on the new platform. This ramp up/warming period is to let inbox providers understand you’ve switched platforms and that you are a legitimate. By sending fewer emails to a more engaged audience, it’s building trust with the inbox providers and will be much more beneficial in the long run.
Lastly, if you were previously on a dedicated sending domain (or often times called an authenticated domain) through the old provider, you’ll want to follow with a similar setup within Klaviyo. Doing so would allow you to realign your sending domain accordingly. This also extends to any specific backend DNS settings you may have implimented.
I hope this helps!
David