Just as a reminder, Spamming (posting nonsensical posts, one word posts, etc.) with the sole purpose of upping post counts is not allowed.
I'll close this thread now.
There are lots of ways to legitimately post a lot.
A few suggestions: Make a point to welcome new members, we have a few fun word games going on in Paws & Reflect, participate in the Daily Thread (DT) daily, start a new thread with stories about your cat, explore the site - you may find you have questions about you kitty, or are able to help someone out with your experience in one of the Feline Companions forums, and IMO most always has active and lively discussions on a variety of topics (surely one that interests you - and if not then start one!).
Just FYI, here is the breakdown of levels here. As Sang said, you need 300 to have a custom avatar, and then at 1500 you can create a custom title.
Kitten - A resigtered member that posted less than 20 posts.
Young Cat - A resigtered member that posted between 21-100 posts.
Adult Cat - A resigtered member that posted between 101-300 posts.
Alpha Cat - A resigtered member that posted between 301-700 posts.
Super Cat - A resigtered member that posted between 701-1200 posts.
Top Cat - A resigtered member that posted between more than 1200 posts.