SEO is tricky. I'm a web developer and SEO and there's no real "right" way to do it. There's the way that is closest to right and not wrong, and then there's the really wrong way that might boost for a few weeks, but then tank you. If you're in a really competitive market then that could be a lot of prospective members that would never find you.
First, you need to write content for the reader, not the search engines. Make sure that your target keywords are where they should be: the <title> tags, the <meta description> tags, and the <h1> tag. By adding keywords to your <meta keywords> tags you're not going to get a boost in search ranking, you're helping to classify your site. If your market is saturated with coworking spaces and you want to differentiate yourself, maybe try including "office space" or "office rental" in your copy to try and help it show up for those searches. Someone looking for office space may see coworking as a viable alternative and not have known about it otherwise.
There are also other avenues to take to boost rankings. Backlinks help tremendously. If you can get a few links from reputable sources, listing directories, newspapers, radio stations, etc., those will improve your ranking in the engines. However, you are associated with the company you keep so if you get backlinks from less than reputable sources then your ranking can drop, so keep an eye on that.
It also helps to classify your data. If you're not familiar with
schema.org markup, get familiar with it. It helps get you into the knowledge graph which gives you that little boost that you might see when you search for your business name or for your business type. It can also get you into the Local Pack if done right.
If you'd like to chat some more about this I'd love to help out. I'm jdflynn on the coworking leadership slack team. Feel free to reach out!