Domain redirect

[chapulin]

Hello, I'm a new user and in the process of setting up my online shop using PrestaBox. My shop's URL is http://gangas-extremas.prestabox.com/. I'd like to redirect my domain www.gangasextremas.com to my new shop http://gangas-extremas.prestabox.com/.

I was told the following after contacting PrestaShop's customer support:

"You can use your own domain by rerouting your DNS A entries to the IP 213.186.52.100
Then send us an email with the domain and we will configure for your shop."

I plan to send the following instructions to my domain host:

gangasextremas.com. CNAME http://gangas-extremas.prestabox.com.
http://gangas-extremas.prestabox.com. A 213.186.52.100

My domain host charges me US$5 to make the change, and I'd like to be sure that I give them the correct instructions for the change to be effective.

Are these the correct instructions to be given to my domain host?

Thanks!