How big do you want this to be?
I started a small comic a few years ago..with the aim of putting out a new one each day...made it about a week before i gave up.
I cant really give my secret away..but it would be funny...well if your a internet helpdesk geek it would be

But i just started off basing it around the same style as garfield.
Small simple..dry...trying to keep it down to just 3 boxes.

do it i am starting comic book series with a fiend and its about my based on my brother its going great

Just make something nice and easy for you. If you like the results, maybe you can have a go on something more difficult next.

I like your idea of making something about you and your cat, you should start there, Just some slice of life. It is sweet.

My only advice would be to read some great comics that have already been done, see how characters are developed, and how the artist has translated the story into organized panels that tell the story in an easy way.
I would recommend reading
*Y, The Last Man*
*Watchmen*
*Dangergirl*
*DC, The New Frontier*
*Batman, The Dark Knight Returns*
*Batman, The Long Halloween*
(The Dark Tower series is pretty amazing too)

There are also several great books on the subject,
*How to Draw Dynamic Comic Books by Rich Buckler and Stan Lee*
*Drawing Cutting Edge Comics by Christopher Hart*
*The DC Comics Guide to Pencilling Comics by Klaus Janson*
*Making Comics: Storytelling Secrets of Comics, Manga and Graphic Novels by Scott Mccloud*

I got nuthin :'< You could ask ^Cedarseed though! She's a great comic artist

You been reading Garfield? Which is pretty good three-cell-comic. They are updating online so do a google search on it. Nemi is also a good advice to follow.

i have never attempted a comic but i do read alot.

make sure your art style fits the format you plan to put it in and as well as making it doable. you don't want to end up being a slave to that comic.

story. make sure what ever you plan to do you have a rock solid story. after that, you can pick up everything else as you need it from books. (raid the bookstore. browse alot, remember them all and buy only one or none)