Cracking is unavoidable, provide ample stress relief cuts in the pour. Use
wire fabric or rebar. Try to pour it (each part) all at once or at least
within 1 hour, this may require a delivery of premixed or rental of a larger
(1 yard) mixer.


I don't understand why people insist on this. For a long skinny
sidewalk, maybe. I mean, I could do it, but it would be cheaper
and easier to just build a raised steel walkway. But there's no
excuse for not being able to pour a simple floating slab the size
of a one car garage without it cracking.

People have built oil tankers out of concrete. It's just a question
of making the extra effort.