1. Start with a Wordpress website on your own hosting.
2. Add in a Google My Business (GMB) account, use a "service area" vs an exact address. A service area is fine if you work from your home and want to hide your home address. GMB will put you on the local map and give you the knowledge box in search if you search for your company by name.
3. Start building targeted citations, Angie's List, Porch, etc.
4. Build "pages" for the business on the top social media platforms, Twitter, Facebook, Google Plus.
Then make your website helpful with content on cleaning tips and tricks. Brand yourself as an expert and share to your social media each new piece of content.
It's going to be hard to rank because the competition is fierce. But if you can teach Google about your 'entity" you have a good shot.
Start by creating a professional look and feel for your business. A website with information about you and your company can be set up easily on Wordpress or Wix. Then you would need some business cards and a brochure that you could drop off to potential clients. Professionally made is better than printing on your printer at home. Costs are minimal and the results are much better. You don't want to look like a fly by night business. You want a professional appearance to create trust in your product/service.
If you have a company vehicle, professional lettering is definitely a great way to brand your business. A great vehicle lettering job gets thousands of impressions while you are out and about and on jobs. Many of our clients get new business and great referrals this way.
You don't mention if you are doing home cleaning or commercial cleaning. With home cleaning, I would ask friends on Facebook and other Social Media outlets for some referrals. The same for business to business. Going in to talk to a potential client through a referral always increases your likelihood of getting the contract as you have been referred by someone they trust. As you gain new clients/contracts, ask them for referrals. Local business groups like your Chamber of Commerce, BNI, etc. are another great way to get new client referrals.
Don't forget online groups like LinkedIn and others. This is a great way to meet other business owner's who might need your services or have associates they could refer you to.
And of course good old fashioned Cold Calling! Nothing works as well as a phone call. Emails go unopened most of the time. Try contacting the Procurement or Purchasing Departments at companies you would like as clients and find out what the procedure is for getting a contract and who the appropriate contacts are. In your field, I would imagine it would be the Facilities Manager.
You have not indicated where you are based. This is very important as local legislations are different in different countries and in Federal countries such as US, Spain, or Germany are even more comlpex as they could vary from State to State.
The best thing to do is to contact a local lawyer and make sure they are specialists in commercial contracts and have experience of your field. There is a simple measure for their experience! Ask them if they have got a contract already which they could modify for your company. For example our lawyer has dozens of standard contracts for different activities and he uses them as the base line, which he then modifies for any specific conditions or terms his client wants to add.
This is usually a good test of the lawyer's expertise and experience in your field. If they have to write up a brand new contract it means a) it will be expensive and b) they have no experience your field, in which case you should walk away and find another one (there is no shortage of lawyers!).
Your contract is one of the things you should not try to do on the cheap as it will cost you dearly later.
Hope all works out well.