Well, you have your work cut out
You will need a source of food for babies, some sort of amphipod, Aremia is not a diet suitable for baby octos and has a proven bad result.
The eggs could hatch in 30 days depending on temp.
The female may keep eating for a few more days depending on when the eggs were laid
Batch rearing babies in a tank fulll of live rock and hiding places may be the way to go rather than small individual tubs, at least to start with
Do a search on TONMO.com's search engine and there is a lot of posts about rearing briareus,, none 100% positive yet

but there is some good info there
check for posts by Nancy, Alicia and dbbga regarding briareus
good luck