What are some proven email marketing template styles I can use?

If you're going to use templates, I always prefer building my own and reusing them. This helps maintain brand recognition, as well. 

But some tips for templates:

• Keep them simple and minimalistic
• Make sure they are responsive (people read on many different devices)
• Keep it segmented and personalized 

There are some tried-and-true template styles, based on the type of email you're sending, such as: 

1. newsletter
2. infographic
3. event/invitation
4. grid-based
5. promotional 

My best advice would be to find and personalize (or create from scratch), templates for each of the types of emails you send out. Then reuse the corresponding template each time. Keeps it simple for you and the reader and they'll be able to recognize your emails on sight. 

Normally if you use text based html email template then you will get higher email deliverability to Inbox.Please don't use many images in the html email template .Keep it simple.Don't write the email content too big .Use unsubscribe link at the bottom.Use link shortner if your website link too long. Use custom tracking domain for tracking your email campaign.Don't use any email company default domain as mail tracker.