All an editorial calendar is, is a scheduled-ahead list of what you're going to post and where you're going to post it. It's easy to do, and even if you don't do blog posts or magazine articles you can include social media posts to make sure all of your accounts are covered regularly.
I use google calendars to schedule my blog posts, social media, and magazine article deadlines. Since I tend to post the same type of topics every week, I can type it in once, then choose the "edit event" function to schedule a recurring event. It will post for the same day every week, or as often as you tell it to.
I have my YouTube posts, cake photo posts and business posts all included. I also put in my newsletter and magazine article deadlines so that I finish those ahead of time.
But the one that will save most people the most time is the social media one...One day a week I schedule a bunch of social media posts, either through the platform itself, or through Buffer, which I love. You can also use Hootsuite, which is free for up to three social media accounts, but it doesn't schedule Pinterest posts, which is one that I use a lot. I have Twitter linked to my Facebook posts, so facebook posts will be shared to Twitter automatically.
I'm still "live" on social media for most of my posts, but scheduling allows you to reach your account followers on a regular basis even if you're busy with something else. I was on vacation a while ago and scheduled a bunch of posts ahead of time so that I didn't have to think about it.
If you schedule AT LEAST your social media posts, it will save you a lot of time, because it will keep you offline. Being online is the biggest time-waster there is for most people since you never do JUST what you intended to do when you fire that computer up. There are always a lot of shiny things to check that end up taking half an hour instead of the two minutes you intended to spend online.
Color code tasks on your calendar then delete them when you do them. Crossing things off of a list is very satisfying. Hitting delete is also very satisfying.
Try it and see if scheduling things works for you. If it doesn't, don't bother keeping it up. But for most people it's a useful tool to keep you on track.