My weekly manufacturing newsletter, The Prepared, has grown significantly in the last few months. I had more signups in August than any month before, and I've been proud to recognize more and more of my subscribers for having done work that I've admired in in the past.
As it's matured, I've gotten a bit better about knowing what I - and my subscribers - want from it. Here are a few guidelines I use currently:
Be focused. While I might fancy myself capable of commenting intelligently on a wide range of topics, the fact of the matter is that while people will appreciate the "manufacturing guy comments on other random subject" link, they won't love the "random guy comments on whatever he wants" link.
Have a voice. I'm with Joe Biden on this: No matter how well it pays, I don't want a job that doesn't allow me to be me.
Be pithy. I tend to pontificate, but this is a weekly email. Try to keep it short.
Be warm. I tend to be skeptical of things I don't have personal experience, but the point of the newsletter is to connect people with interesting stuff. Where appropriate, show a little enthusiasm :)
Differentiate yourself. I subscribe to a few great newsletters (check out Jon Russell's, Reilly Brennan's, Alexis Madrigal's, and Benedict Evans's), and will definitely repost stuff that those guys share. But ultimately it's good for me to have my own niche, and defining myself in opposition to them helps make The Prepared better and more useful to my subscribers.
Don't stress the format. The categories are useful for organization, but they really don't matter that much.
Attribute links where it makes sense. This is a tricky one, especially because my workflow (which is 90% Pocket, 10% IFTTT+Gmail) doesn't make it easy for me to remember who sent me what. As a result this ends up being mostly driven by practical constraints, like whether or not the person who sent it could use a shout out, and whether or not they have a web presence that I can link to, and how well publicized the thing they sent me was. Not exactly a science, but I try.
This is a weekly email, but the actual day I send it out doesn't really matter. Some people may feel differently, but my rule is that I need to send it "sometime in the weekend," and I define "weekend" liberally.