Some topics are too large to be a single post. As you write a post ask yourself if you need to step back and deal with other related subjects as well. If so, then you might have a good candidate for a series.
The best way to write a series is to start with your recap post. This is the post where you link back to all the posts in the series so people can find them all from one place. Write this post first and list the different posts that make up the series–even though you haven’t written them yet. Then take this list and write a post for each item. Sometimes it is easiest to do this in a text editor so you can see all of the posts at once. This lets you jump back and forth if you find a better way to organize something.
Once you have the series written, post each one to go live over a period of time. Usually you’ll want them to go live every day or on a particular day of the week. For example, you could post one item from the series every Wednesday for the next 5 weeks. If your series is only of interest to a subset of your readers, then doing a post on a particular day of the week is probably better. You don’t want to alienate half of your readers with a 10 part series on something that doesn’t interest them. If is a single post each week, you are less likely to lose readers who aren’t interested.
When you post a series, do an introductory post to let everyone know what to expect. Once the posts are all life go back to this post and add links to the series. If someone finds the introduction weeks later you want it to be easy for them to navigate to the posts.
Your summary post should also contain links to all the posts in the series. It is a good idea to post this at the end of the series. A similar recap a few months (or even years) later can help point people back to your content and make it easier to find.