To make your website ‘bigger’ and ‘more active’ tells me right away to start writing articles or blog posts to your website. By providing content you gain a sense of ‘authority’ that Google considers in its ranking algorithm. It also gives your website a sense of authority to make it look ‘bigger’. Adding a FAQ (frequently asked question) page also gives a sense of professionalism and authority to help you in this area as well. I would do some keyword research or visit areas like Answer the Public to get ideas on what people ask. Soon enough you will start gaining more traffic from the blog posts, articles, and FAQ page to give your website a more ‘established’ internet presence.
To make it more active I would provide a feed of your Facebook page and new stories that relate to your industry onto the home page of your website. The new version of WordPress allows you to display feeds from other websites but when people click on the links for the feeds it DOES NOT open in a new tab so you will have to install a ‘feed plugin’ to make it open in a new tab. Ideally, it would be nice if you can open the link into a new smaller window so that they can see your website in the background.
Why do this? Because you do not want people to visit another website then close the tab thinking they will go back to your website but it will be gone. Another thing to take note is to make sure that the feed that shows news of your industry does not show your competitors. You wouldn’t want to send people to your competitor’s site instead of yours. You can view the feed of what you want to use and see where their past feeds compromise lead to. If you use a plugin you can decide which posts go through and which ones not to display if you have the time. Otherwise, it can be done automatically for you.
Another way to make your website more ‘active’ is to install a forum where people can get together and discuss topics. This is only effective if you already get a lot of visitors to your website so I would put a hold on this until you do. I have found that popular posts have people leave comments and talk to each other a little bit that way.
Making the website more interactive with the general public is another way to make it more ‘active’ as well. Here is a Google Search on how to do this.
Santos Halper requested your answer