Keep these things in mind when pouring a DIY concrete walkway. Set a level frame with one-by-four lumber. Lay plastic on the bottom, so the concrete cures more slowly, resulting in a stronger slab. For a larger area, add steel reinforcing. Spread the concrete evenly, lifting the rebar into the middle. Finish off with a steel trowel or a bull float for a smooth surface.

For more on cement, consider:

9 Easy Concrete DIY Projects
Bob Vila Radio: DIY Concrete
How To: Make a Concrete Walkway