Make a prototype board using ARM core
Manufacturers usually want to make it easy to use their chips - as such there is often a reference design in the documentation that will show you how to get it up and running.

Taking a quick look at the documentation page for your chip shows that Atmel has provided a Schematic Checklist. This will give you tips on how to hook up the power, reset, clock and other support circuitry.

You'll also need to consider how you will load software - does the chip have a preprogrammed bootloader (USB or serial say) or do you need a hardware programmer (JTAG etc).

If you're new to this, you might find that it's easier to get started with something like an 8-bit AVR. They can run off 5V from USB so you may not need a regulator (whereas most ARM micros run at 1.8-3.3V). They also have a simpler interrupt model, come with an internal oscillator and you can get them preprogrammed with a bootloader from some suppliers.

Good luck with your project whatever you choose :)