I am going to try and create a dual boot USB stick following your instructions. What size do you recommend making the three partions, especially partition one and two?
Hi, sorry for the late reply.
It depends on your habits.
FYI, in my case above, I used an old 8G pendrive.
The sizes are roughly 4G, 512M, 3.5G in order.
4G for file sharing, FAT32.
512M for bootloader, FAT32 EFI.
3.5G for TC stuffs, ext4.
Note that, the first M$ partition is totally optional.
It's for file sharing between the operating systems.
Since M$ only accept one partition for an USB flash drive,
you can't access files in other partitions.
The M$ policy usually assign a letter to the first partition on the USB.
Thus, the first partition exist.
If you don't need to share files between the systems,
then you could omit the first partition and merge partition 1 and 2.
About the file sharing, here's a brief example.
Say, I'm learning C language.
I'm currently working with it under linux system.
In order to test it out on M$ system,
I can just put it in the first partition of the USB,
and reboot my PC.
When the system comes up,
I can load and edit the file normally.