Decide what kind of comics or comic books you are looking for. You can choose popular newspaper comic strips such as Calvin & Hobbes, Garfield, Peanuts, Pickles, Mutt & Jeff, For Better or For Worse and more. There are also editorial and political cartoons for free from many popular newspaper cartoonists. A few comic books are available online as well.
Try doing an online search. You can make your search general, such as "free comics online" or "free comic books online". You can also narrow your search if you are looking for a specific comic type, such as "free political comics online", "free Garfield comics online", "free Marvel comics online" etc.
Check with online newspapers, or search to see if your favorite comic strip has a website where you can view comics for free. Also look for web sites that offer multiple types of free comics online.
Consider reading comic books online. You can find a few selections from popular companies such as Dark Horse Comics. They offer free original content in their MySpace Dark Horse Presents series. Other comic book companies sometimes offer featured selections or digital samples that you can read for free on their websites or some offer what's known as free Ecomics. Check with comic book companies or comic artists that you are aware of to see if they offer any free selections.
Look for comic books in the public domain. These are usually vintage online reprints of classic golden age comics whose copyrights have expired.
You may also find new comic book makers or artists who offer free online comics to get exposure.
Try doing an online search using search terms such as "copyright free comics", "creative commons comics", "public domain comics" etc.
Use the instructions given on the web sites you choose. Some sites may require registration. You will find comics and comic books offered by download or some that can be read directly online.
You may want take advantage of features offered by some sites that notify you when your favorite comics are updated. You can subscribe to RSS feeds or sign up to be notified by email.
See examples of web sites where you can find free comics and comic books to read in the resources section below.