Increasing the deliverability of your email marketing campaigns doesn't require that you become a hacker - it's a simple process of making sure that email clients (e.g. Gmail, Yahoo!, Outlook etc) know you're sending out legit newsletters.
The most crucial thing to do is to verify both your DKIM and your SPF records. Most popular hosting providers make the verification process very easy. But since you're here you've probably done both, right? You should!
To check if your DKIM and SPF verification was successful just follow the steps below:
A. Checking your DKIM key
1. Visit http://dkimcore.org/tools/keycheck.html.
2. Fill-in "ms" in the Selector field and add your domain name on the Domain name field. 
Pay attention that you don't use "www." when adding your domain name.
3. Click on the Check button. 
4. Check that your DKIM Key is valid and what its value is. 
It is highly advised that you compare the key to your DKIM records in Moosend.
5. Click on the Accounts button, located on the top right side of your Moosend account.
6. Click on the Senders option on the menu that appears. 
7. Click on the sender's email whose DKIM key you want to check. 
8. Check the DKIM key in the designated TXT record value area. 
B. Check your SPF records
1. Visit http://www.webtoolhub.com/tn561347-mx-ns-soa-record-lookup.aspx.
2. Fill-in the full domain name on the Enter URL field. 
You should include the "www." this time!
3. Click on the Show button. 
4. Check that your SPF Records is as shown. 