It's always so much easier to let the hen do the work! If you've got a good broody, she's worth her weight in gold! When I want my Australorp to go broody, I get some of those ceramic eggs from the feed store and leave them in the nest she usually lays in. That way I don't have to leave eggs that might otherwise go bad waiting. Within a few days, my Australorp usually notices these and starts sitting on them. I do a switcheroo at night - Indiana Jones style, reach under her and switch the porcelain eggs for real eggs! She has yet to notice anything was amiss.
A couple of "beware" notes ... First, make sure your broody takes care of herself. Make sure she eats and gets water. You might isolate her if it seems like the other chickens are pushing her aside so they can keep laying in the nest! Last, a good broody does not necessarily make a good mama. My stupid Australorp will hatch anything, but then she's something of a bull in a china shop and tends to trample chicks. I let her hatch them, then I put them in a brooder inside.
