How would I mill this?

[cncJim]

Hi everyone,

Sorry, this is probably very simple but....
I would like to make a pen holder for my cnc machine - Like this:-



I'm not too bothered about the pen holder really, just want to understand and gain some knowledge of milling techniques involved in creating something like this. I would like to mill this out of aluminium and be as accurate as possible. So if someone could break down the idiot proof steps needed to complete the job I would be very grateful! :)

Im guessing starting with a piece of aluminium like this maybe:-



Thanks for any advice,
Jim