Get on the phone and get on the Internet to gather all the information you can stomach. Call agencies and ask for advice or referrals. Go through a few interview and application processes with them. Make sure to read "Working with Domestic Agencies" to know the behind the scenes of what to expect. One of the best agency situations is a temporary agency. It will take some legwork to find one that has domestic or combination positions (domestic/executive), but this is one of the best ways to get experience with house management or personal assisting. For example, if you can get a job assisting a busy executive in their office, look for a situation where you can manage the personal duties as well. This includes gift buying, personal errands, pet care, scheduling and overseeing work at the residence, personal travel arrangements, etc.
Although classifieds are one of the oldest ways to search, they are also one of the best. Often employers will try their own search before calling an agency and those willing to hire for a "starting" position probably won't use an agency. Check in the papers local to where you want to work and live. Most papers put their classifieds online, so check the Internet as well. Another great source for ads is the Caretaker Gazette. It is the only paper specializing in ads for caretaking and professional domestic positions, with some nice related content. Look them up online or call for information at (715) 426-5500. Another great feature of classifieds is that for a small fee you can place your own ad looking for the right employment situation.
If you are good with people, put the word out on the street about what you're looking for. Tell friends, relatives, former employers, etc. and start spreading the news. Most of the positions in the domestic service industry are filled this way. If you were looking for someone to work with your family and home, wouldn't you ask a trusted friend or associate? Of course. Just by getting your name in the right social circles you could end up with an amazing job. And perhaps a good showing will lead you to the next family on a referral from that one, and so on. Many long-time domestic professionals never go through a job hunt and frequently receive offers from friends of their employer. That is the level to aspire to.
There are several schools to train you in domestic service. This is a path for the truly committed, so as before, step one (conviction) is VERY important here. Schools are fairly expensive and do not guarantee placement upon graduation, but certainly the knowledge, experience, and dedication it takes to complete the courses is a step in the right direction. Also, each school will have a placement service or leads for you to network for a job. (More resources!) Consult with the different programs out there to see if it makes sense for you based on your goals and your finances. The better ones are listed on modernbutlers.com
In conclusion, a few basics are important to get started in the private service field: Be sure of what you are after; be prepared for the opportunities; and use all available resources to give yourself the "lucky" break into the business.