The key theme from the SXSWi Panel “How to Make a Living as a Blogger?” It’s not easy. Panelists Brian Fairbanks and Colleen Kane discussed the challenges a potential professional blogger faces.

Some of the highlights:

Some of the silliest topics get the most hits. This is something a blogger has to balance. Do you really want to write about hot actresses or top Hollywood bodies? Sex is usually the easiest topics to draw traffic to your blog. Also, “top” lists are huge hit-getters, especially if they are about sex. Sites like Digg make these lists so easy to find and draw huge traffic to your blog.

Start writing your blog and eventually ask people writing similar things to help contribute. Not only are you getting free content, you’re also getting 100% of the traffic on your site.

A professional blogger in the crowd suggested bloggers should sell their brands to companies to help their brand. For instance, this blogger writes about parenting and sold a “road trip” blog to GM.

Another person in the crowd said if you have a niche blog, let a company know if you are writing about its products. It could lead to great publicity and more opportunities to write.

Bottom line: becoming a professional blogger takes a lot of work and a lot of patience. Most importantly, it takes passion that you can market.