Optimizing web pages from top to bottom is the very basis of on-page SEO. It gives your site a chance of showing up in the search engines and create a better user experience for visitors. Some of the things that are involved in performing SEO on-page are:

Quality Content: Creating content that is worthy of Googles E-A-T (Expertise, Authoritativeness, and Trustworthiness), is a huge step when creating any content.

• Content Length and Readability: Knowing what reading level and how many words to write based on the top ranked pages in Google search results is key to competing.
• Keyword Optimization: Be sure you integrate keywords correctly in your content. Bruce Clay makes a great WordPress SEO plugin that offers you a wealth of information.
• Meta Data: Put some effort into creating meta tags for each page. In addition creating the title and description may be the first thing a visitor sees in the search results. This tells Google what the page is about.
• Image Optimization: Ensuring your images are optimized, as well as all of the elements of your website, help you gain visibility in other parts of Google such as Google Images. This helps boost your visibility in the main search results. Ensure you include ALT tags on your images to ensure you take advantage of it, in addition, the Americans with Disabilities Act states all websites should do this for the vision impaired anyway, so you knock out two problems with one stone.
• Heading Tags: Heading tags within a page or article create the subsections of the webpage. Ensure they are properly formatted heading tags. This will allow your visitors an easier to read experience and will signal the search engines on what topics are covered on your page.

For more on-page SEO ideas, check out this Complete SEO Checklist for 2021.