The blog design should be inviting and fresh. I envision a design that is colorful, entertaining, and has a hint of pop-culture sensibility. At the same time, the design should be clean and organized. I'll discuss fantastic and exciting web sweepstakes and contests. A cool logo will be needed. The tagline will be something like "A daily discussion of fantastic web sweepstakes."
The blog will be a 2 column blog. The left column will be for content, ie blog posts.
The right column will be reserved for things like ads, widgets, most popular posts, etc.
Each post should have social sharing buttons for sharing the post via email, facebook, and retweeting.
Also, the blog itself should have Facebook, Twitter, and RSS buttons for people who want to follow or subscribe to the blog.
For a sample blog entry, see (content only, not design):