Heres how I made a multiboot stick with OSX (for hackintosh - don't put this anywhere near a real mac!), Windows 10 and Xubuntu. Firstly, follow the tutorial as outlines above. This creates a usb installer that uses the whole disk. Once thats done, and you have installed clover continue: Launch disk utility. Select the usb stick and choose "Partition". Add the number of partitions you need. I have 3. You can add more (suggest max 4, and make the 4th ExFAT, for driver installers and such). Adding Xubuntu to the stick (or any linux you desire): In disk utility, format the partition you want to put the linux live cd on, to "MSDOS (FAT)" and give it a unique label. I called mine X, as Xubuntu is what I am using. Open terminal and type diskutil list Find the disk identifier for the linux partition. Mine was "X" disk4s3 Download unetbootin Download a linux distro live CD Open unetbootin and type the mac's password In unetbootin select iso and click the 3 dots. Find your iso, and select it. Then select the disk identifier you found earlier with diskutil list, and click go/create/whatever the "do it now please" button on unetbootin is. This will take care of the linux part of the stick. Windows: In disk utility, format the windows partition with filesystem "ExFAT". We'll change it later to NTFS since mac os doesn't handle NTFS writing natively. This just helps us identify the partition so we don't accidentally blow away the wrong one. Give it a unique name (I chose "Windows 10") Grab a copy of Tuxera NTFS (google it). This gives NTFS read/write support. It also allows you to format partitions to NTFS. The trial version is fine. Paragon 15 will also work, but Tuxera gives a 15 day fully functioning trial if you only need to use it for this purpose. Open Tuxera and locate the windows partition on the usb stick. After clicking it, in the right hand pane, select format, from the dropdown list select NTFS, and name it appropriately. Once its formatted, you can simply double click your windows 10 iso to mount it, and copy its contents to the windows partition on the stick. A UEFI bios will have no troubles finding and booting it. To be safe, try and use the latest version downloaded from MS, as it includes drivers to handle fancy things like NVME drives and usb 3 only motherboards. Finally, format the last partition with ExFAT, and copy any additional stuffs to it, like clover configurator, clover installer, windows drivers, and any other items you may need, such as an antivirus, or a backup of your EFI folders contents for example. Now you may safely eject the stick. Take it to the target computer, mash f11 or whatever key the bios assigns to "boot menu" and you'll see 3 entries for your stick. The first will be clover (to boot mac os for a hackintosh), the second Xubuntu, and the third windows 10. Ok so this process means you need to recreate your stick, but now I have a tribooter for fixing mates PC's and hackintoshes, I keep a seperate stick with just the first part of this thread (the terminal command, no clover) for working on real macs. Xubuntu has come in real handy for killing stubborn virii on windows PC's!