Just go to your local store and get some chicks, or have them ordered in. Now it is relatively easy to get chicks, and you can order them so they come in when you want them. And you can get pullets. If you hatch eggs, nearly 50% will be roosters.
If you want, slip a couple of golf balls under her. Won't hurt, and might help. Leave her where she is, and let her be.
Then when you get the chicks, bring them home, make sure they all have a drink of water! Then put them outside in the coop, and let them get a little cold for 30-45 minutes. Sounds heartless, but do it. To make the bond between chicks and hens, it has to go both ways. The hen needs to want the chicks (their motion underneath her, triggers that hormone.) and the chicks need to associate warmth and a saftey with the mother hen.
I take the chicks down in the near dark, with the smallest of lights, and I am wearing a thick sweatshirt. Then I cover the hens head with a towel, and start shoving chicks under her. There is a lot of empty space under a hen. She may peck at them, if they crawl out, that is ok. But if they are chilled enough, they are going to burrow in tighter than a tick to that warm spot. That is what you want.
Then you have to do the hard part. Shut the coop and leave. Do not watch, do not interfere, do not try and protect the chicks. Her voice should change, and she will nearly constantly cluck to the chicks.
Do not worry if your nest is off the ground, she will manage it. The day before chicks, I do a sweep out, and put fresh bedding on the bottom of the coop. I no longer make a nest for her, none of them have ever liked my efforts. She will get the chicks down, and make a new nest on the floor.
I do put feed and water in the coop at this time. But do not put it by the nest. Leave it there only until she takes the chicks out to run. Which is usually in 1-3 days. And then just watch and enjoy, while she does the work.
so, is she still on the nest? Is she as flat as a pancake? Does she seem like she is in a trance? Does she puff up like a beach ball if you get too close? If so you have been blessed with a broody hen!