Hey, Patrick. Welcome to C-C and the writing life!
Your question on profiles is a good one. I'm a firm believer in profiles, myself. Post a good photo of yourself so people can connect with you on a personal level. In your bio, don't mention that you're just starting out or don't have a portfolio--that reduces trust. Instead, make a short list of topics you're interested in writing or researching. You can mention your education if you like, especially if it's an MBA or a PhD in physics or something wonderful.
The key with a bio is SHORT is GOOD. Don't post your resume. People stop reading after the first three or four sentences anyway. Get to the point and put a "call to action" at the end--something like "I'm looking forward to working with you" or "Send me a private request to let me know your topic" or something. Just use your own voice for the invitation.
Profiles don't actually sell your articles, they sell you. 99 percent of people don't read bios (I'm in the 1 percent category, I love to know about my competition). However, if you don't put something in there, people will think you're not serious until you've got a hundred or so articles in your portfolio.
One final note on your profile: C-C doesn't show your personal "recently sold" content. Since I write on a variety of subjects, I've put my recently sold titles in my profile so people can see that I write home improvement articles as well as the gardening articles which are showing up on the first page of my portfolio. See how that works?
Write an elevator speech of 50 words or less and post it. Then you'll never have to do it again--use the same one over and over throughout your career.
Good luck!
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