A business using social media needs a marketing plan and a content strategy to support it. It can be overwhelming to try to create and publish great content. But even if you are only an individual using social media across platforms, you need to get organized.
A pretty standard way of doing that is to schedule using a content calendar. I have one for my client work, but I also have one for my personal blogging which happens across six blog sites. I want to have regular content out there but I don’t want it to publish all at once, and I can’t keep up with writing it all at once either.
Your plan is a template, a calendar that shows all your channels and when things will publish.
Anyone with multiple accounts will find it useful to use a scheduling tool, like Hootsuite. They offer a free version and a pro and enterprise edition. I have used all of those versions and the basics found in the free version are a good starting place for anyone using social media.

image via blog.hootsuite.com Download a spreadsheet version to use
A content calendar helps you curate content. It is an editorial strategy.
Using the analytics available in the paid versions also helps you know your audience and decide when (time of day, days of the week) to publish, who to follow, keywords etc.
I organize my content calendars by social networks (Facebook, Twitter etc.) for each week by days and times.
For one client, I am part of a team, so there are several of us creating and scheduling and the calendar and Hootsuite allows us to work without stepping on each other. But even on my personal accounts, it is too easy to accidentally schedule posts that conflict with each other.