[Theme: Twenty Eleven] Add widget to site header.

Do forgive, I’m new to wordpress .css .php & programming in general. I’d like to widgetize the header area right of the site name and description in the twenty eleven theme. I’ve read previous posts/threads and wp links concerning widgets, but I’m looking for a simple step by step explanation. I have created a child theme with nothing after import style.css, but have not uploaded/installed it as I didn’t want to miss anything. I’m considering this plug-in, but I’m still uncertain the location to insert the accompanying code (or if this is a legitimate solution). Any assistance is greatly appreciated.