Use your name. When writing Emails to your users always personalize it.

1. Write Your Email Subject Lines for Mobile Devices

2. Keep Your Email Subject Lines Short

3. Personalize Your Email Subject Lines

4. Include Multiple Topics in Your Email Subject Lines Examples:

https://blog.kissmetrics.com/your-next-email-subject-line/

https://www.crazyegg.com/blog/email-subject-line-hacks/