There can be different reasons a homemaker will desire to have help at home, for instance a growing family, weak health, a big house, husband working long hours etc. Before hiring someone determine how many hours you want them to work and how much you are prepared to pay. Be careful about people you allow into your house, especially when small children are involved or you are vulnerable in any other way.
When interviewing the prospective help, try to find more about her background and working experience and on your part, tell her what tasks she is supposed to do, how many hours exactly you expect her to work and what her wages will be. Your new cleaning lady is your employee so you should treat her as such. Be polite but firm, don't get too familiar, don't pry into her affairs and don't gossip about her - it's extremely bad manners.
The first working assignment is crucial as you can observe your help in action so to say, discover her weak and strong points and decide whether she is really suitable for your household. It's better not to leave her alone, at least in the beginning before you can fully trust her. Don't expect perfection and be flexible. If your help is better at scrubbing the floors than at ironing, let her do it and iron yourself.
You shouldn't ask her to perform dangerous or very unpleasant tasks such as cleaning a cat toilet or washing windows outside on the third floor. After two hours of work, your help is entitled to a cup of tea or coffee with a cookie. It's also good manners to give her a bonus with vacation and a present when she quits.
It makes things so much easier to have a cleaning plan or schedule and discuss it with her so that both of you will have a clear idea of what she is supposed to do on any certain day.
I hope the information above was helpful. If you have any questions, feel free to ask!