Create unique, valuable content.
For starters, your site could be initially approved by Google AdSense, but later reviewed for quality assurance. In other words, you can't fill your site with low-quality content to get 100 pages indexed and monetized.
Instead, find something you are passionate about and find other people who are passionate about the same thing. Then work together with them to create the kind of content that other people who are passionate about that topic would want to read.
Make your site sticky.
Visitors to your website might not click on your AdSense ads right away, and if they leave after looking at just one page, you've likely lost them and their potential AdSense earnings forever. That is why you need to create a site that is sticky.
What this means is you need to make sure that every visitor that comes to your site wants to dig deeper and deeper into the site. There are several ways to do this. For starters, have clear navigation at the top of your site so that visitors can find the best parts.
Next, make sure that every piece of content links to more pieces of content. That way, if your visitor isn't enjoying the page they landed upon, they might see a link to another topic they would be interested in instead.
Finally, have more content links in the sidebar. Let your visitors know what your most popular content is, what your most shared content is, and what your most commented upon content is. Visitors will be curious why those particular pieces of content are so popular, and that will keep them on your site even longer. And the more times your pages get loaded, the more ads they will see, leading to more potential Google AdSense earnings.
Give your visitors multiple channels back to your site.
Don't let your visitors forget about your site. Your header, sidebar, end of content, and footer are the perfect places to include multiple channels that visitors can connect with you so they can follow you. You should include options such as email opt-ins and social networks. That way, each time you produce or promote a piece of content, you can remind your visitor about your site and hopefully get them back to potentially click on more of your AdSense ads.
Optimize your user experience.
One thing that hurts many site owners is user experience. You may have the greatest content and the best ad placement possible, but if your site doesn't load on mobile devices or loads slowly, you could lose a lot of your visitors long before they get the chance to consume your content or click on your ads.
That’s why it’s essential that you do a couple of things for your site. First, run some simple tests using Test My Site with Google to make sure your site works well for mobile users and loads quickly. If your site has any issues, both of these tools will point them out to you so you can fix them.
Second, sign up for Google Analytics and Google Search Console if you haven't already. Google Analytics will allow you to keep an eye on your traffic levels, so if you see a drop, you can look into it right away. Google Search Console has a wide array of tools that will help you find out if your website has any performance issues or other errors that could be causing your visitors problems.
The best part of all of the above-mentioned tools: they are all free (some with premium options) to improve your site's user experience!