After a while browsing different tutorials on how to install tails onto a usb stick using a mac and to be bootable on a mac, i discovered a small amount of confusing ways. Some of these methods involved using third party applications and some involved multiple USB sticks or CDs... All over worked and not needed.
Thats why i have written out the below instructions to help you install tails and other such iso programs onto a USB from a mac.
Step 1 - Download Tails
You can download tails from here, Download Here. I would suggest using the firefox browser with the plugin.
Step 2 - Convert the ISO
To make this possible we need to now convert the ISO disk into a DMG image. Todo this simply CD into the directory containing the ISO image and run the below.
To CD into a directory use
To convert the ISO image use
This is assuming the ISO image is on your desktop and you have CD to the Desktop directory using the above.
hdiutil convert -format UDRW -o tails-amd64-3.0.1.img tails-amd64-3.0.1.iso
Step 3 - Install onto the USB
Now you are ready to install the newly converted dmg image onto the USB stick. First, open Disk Utility and erase the device. You want to select Mac OS Extended (Journaled), and a GUID Partition.
Once that is complete you need to run the below commands in Terminal.
Command 1 - Identify the USB
Use this command to find out the USB sticks identifying name. It should be something like disk1
Command 2 - Install
Now that you have the disk identifer simply run the below command. When you run this command if you get an error message stating that dd: /dev/disk1 Resource Busy. Simply open Disk Utility and eject the partition of the USB stick and not the whole thing. Then run the command again and it will work.
sudo dd if=tails-amd64-3.0.1.img.dmg of=/dev/rdisk1 bs=1m
Give it a while (normally about 5-10 minutes), and your done!
You can now reboot your mac and hold down the ALT key to boot from your new tails USB device.