How to create bootable USB from ISO image?

Usually, when I wanted to create a bootable USB stick from some ISO images (when I wanted to update the image, or get a new/different tool), I used Fedora Media Writer [Win/Mac/Linux], or (when I wanted to add a persistent partition) Rufus [Windows]. There's a tool, however, that I got to know only not too long ago, but already really recommend - YUMI!

Recently it occured to me that even with my quite old (when 8GB was a big capacity) pendrive when I write an image (that usually takes up to 2GB) a lot of space becomes fairly useless. So I thought - hey, can I put several ISOs on a single drive?

As it turns out, the answer is HELL YEAH!

YUMI (Your USB Multiboot Installer) is an amazing (honestly, I'm stunned) tool which I would call a booting proxy - after installing it on a selected drive you can simply copy images of your choice into a specific directory on the drive (there is an exFAT partition for that, so it should work on all platforms without any additional tools), and you're done. Seriously, that's it! Need to update an image? Delete what's old and copy new images. When you boot YUMI up, you can browse through the device, and select whatever image you want to start from!