Cheatsheet for cloning an HID tag using a Proxmark3 on a Mac.
Get and build the Proxmark source code.

On my machine this lives in ~/src/svn/proxmark/client 

Connect the Proxmark, find the port and run the software.

The Proxmark device draws significant power, and is not happy working through some hubs, so connect it directly to the machine. On my machine the device shows up as /dev/tty.usbmodem1421. So, ./proxmark3 /dev/tty.usbmodem1421

Clone the tags:

Read the source / exiting tag:

proxmark3> lf hid fskdemod
#db# TAG ID: 2400a724c4 (47212)

Poke the button on top of the Proxmark to stop reading.


Write to a new T5577/T5567/T5557 tag:

proxmark3> lf hid clone 2400a724c4
Cloning tag with ID 2400a724c4
#db# DONE!