Changing my recommendation on the best Related Posts plugin to use. This one is easier to set up and has more options to control what’s displayed. Check it out!
Using Wordpress’s conditional tags can add variety and nuance to your blog. Here are instructions on how to implement them using some very basic PHP. Novice-friendly.
How to use the .htaccess file to deny access to any IP address, whether it’s a comment spammer or just someone you don’t want on your site. And how to build a 403 page which will explain they’ve been blocked (and allow appeals, if you’d like).