keeping your site interesting

There are two main ways to keep your site interesting and to have reoccurring visitors: a great layout and great content. When you make your layout you want it to be unique. Be careful of following trends, you can try them, but try to add a personal touch to it. Experiment with coding and layout designs when you make a new layout. Every time you should try to step a little outside of your coding/graphic comfort zone. Challenging yourself helps you learn more about making graphics and coding.
The content you make shouldn't just be good quality content, but there you should also strive to have and make content that every site doesn't have. Unique content can bring back tons of visitors and bring in some new ones. I once had a "preppy" sign maker and a collage maker on my site. I also had a "Psd Corner" that provided psds for site owners and graphic psds.
Update your site as much as you can. A lot of sites will update every time they change their layout and then become inactive for a couple of months. Try to stay on top of adding new content to your site as much as you can.
Doing contest and giveaways if you have the extra time can help. This really helps brings in the viewers and keep their interest's peaked especially if the prizes and giveaways are really interesting and something a lot of people would enjoy.
Update your blog even when you don't post new content. There are visitors that like to see what you are doing and how you are doing. It lets viewers know what is going with the site and you. Having a single message on your index page can be pretty standard, but having a blog and updating it can help show visitors that you're site is active and great place to visit.