Expression: From scratch

From scratch works like an adverb, and it describes making or doing something from the beginning; starting with no advantage or prior preparation. For example, if you bake a cake from scratch, it means you don't have a packaged cake mix; you make it with flour and eggs, etc. Here are a few other examples:
There were so many errors in the program that the programmer decided to rewrite it from scratch.
When I was a child, my parents and I used to bake Christmas cookies from scratch.
We started from scratch on the project; now I realize that we could have had more help at the beginning.