Making your own email template design can be a fun activity. It's the best way to step forward and test your skills and knowledge in basic programming. However, some hiccups you might experience along the way might spoil the whole experience. That's the reason why I'll be leaving you with a few things to note during the whole activity.
A lot of people who have been making the design themselves complain that their work is not just good enough while some people even think that their work might just as well go to trash. This is usually the reason why they just call it quits and never think about making a template again.
Quitting does not solve the problem. Maybe we just got a problem in the art department here. The working principle in designing the templates is simple. That is to make the design simple and not too flashy.
Simplicity as we know it is always the best. A flashy email might get someone interested but the flash might just blind the reader and take them out of focus to what really the email is all about. Find a balance between the glitters and functionality. I do not expect you to get this all at once, so do not quit immediately. Aside from that, the flash and glitter might just not show itself specifically when there is compatibility issues involved.
Speaking of compatibility issues, these templates can be plagued with compatibility issues specifically if you coded the whole thing all by yourself. Your work may look good in one browser but when you check it on others, it may not just look like how it should be.
Compatibility has always been a problem and has been one of the big reasons why it's better to just have someone do the job for you, but of course, hiring a professional defeats the whole idea of the activity.
To get away with most of the problems of compatibility, it's a good idea to just work on an existing open source or free email template design that's made by a professional. These templates will be more likely void of errors, so it will reduce the chances of getting errors along the way.
Of course, if all else fails and you find yourself trapped between walls, read! There's a lot of material online that you can use.