You do of course have other options. Linux is all about options. But if you want to (and can) go with sophisticated methods which offer many different options, you probably don't need this manual at all.
Manually copying files
This method will give you a little more control over what happens, but in turn, it is a lot more complicated. The official Debian installation guide says:
There is an all-in-one file
hd-media/boot.img.gz which contains all the installer files (including the kernel) as well as syslinux and its configuration file.
Problem is, they don't exactly tell you where the above file can be found.
To download the file, choose from the following locations:
- For 64bit architectures, check here
- For 32 bit architectures, check here
Once you have it, you should extract it to your USB stick
sudo zcat boot.img.gz > /dev/sdX
Then the manual advises to
mount the USB memory stick (mount /dev/sdX /mnt), which will now have a FAT filesystem on it, and copy a Debian ISO image (netinst or full CD) to it. Unmount the stick (umount /mnt) and you are done.
The Debian manual also warns that this method will limit the USB drive's capacity to 1GB, regardless of its physical size. if you want to re-use it, you will need to reformat/repartition it.
There are several GUI tools for burning ISO images to pendrives, one of the most popular being unetbootin. Debian explicitly advises its users not to use tools like unetbootin, for they alter the image.
You might be safer with Ubuntu's Startup Disk Creator, but the best would still be to stick to the command line (see the first option).
If you are interested in some more sophisticated methods, head over to the Debian website and read the appropriate chapter from the official Debian installation manual. The following link is for the amd64 (64bit CPUs) version of the book, but the instructions should be the same for 32 bit as well.
Link: Preparing Files for USB Memory Stick Booting (Official Debian Handbook)