Like to play many different modded maps in Factorio? Wish you didn't have wait through loading up just to sync to a save file or a server then load up AGAIN? Well have I got a tip for you! Just follow these steps and you'll be launching right into different mod packs like a pro!
We start with just a basic shortcut to Factorio on, say, your Desktop.
Right click on that guy and pick "Properties". We'll be working with the "Shortcut" tab.
Your directories will probably be different, so don't change them. We just want to add a bit of command line magic to the end of the "Target:" entry.
Here we want to add a command line option at the end. Here I have added:
Make sure you put the double quote marks around the path just as a habit so it will work with directories with spaces. This path can be to anywhere on your computer, it doesn't need even live in your main Factorio directory. However I like using something like "mods_MODPACK" in my main directory to keep things tidy.
Now that this is setup you can launch straight into the game with this shortcut and it will use that directory to load mods from. Each directory will get it's own toggles for installed mods and even store different mod options.
Congratulations! You're now running mods like a pro!