The best thing really is to go and read the articles on TONMO (i wont add a direct link on another forum but just google it), read the cephalopod forum on here and TONMO and generally get a good feel for their needs before you contemplate setting up the tank.
Be prepared to have a species tank containing a single octo, forget adding them to a full blown reef.
To be honest the articles are a pretty good introduction, us ceph keepers will be happy to fill in the finer detail if you have questions.
I currently have an a. aculeatus, many articles are based on bimacs but they are becoming increasingly hard to source - hummelinki and aculeatus are good choices of a similar size and needs.