Remember you are creating content for your audience. For that content to be effective, it needs to offer value to the reader. Content should always have the purpose of providing information, answering a question or addressing potential pain points.
The content you add to your website needs to engage your audience and encourage them to take the next step, so make sure you include clear calls-to-action.
Google will prioritise content that is authoritative and trustworthy. The more factual, reliable and helpful your content is, the better the chances are that it will be indexed higher in the search results.
If you want some quick ways to find great content ideas, read this post on Free Keyword Research Tools for Small Business.