1. 当according to表示“根据”“按照”时，它主要用来引出状语，一般不用来引出表语：

这本书是根据一个真实故事写的。

正：The book is based on a true story.

误：The book is according to a true story.

但是当according to表示“合乎”“符合”时，可用来引出表语。如：

It is not according to his nature to give praise. 他本性不喜欢颂扬。

2. 对于你在问题中提到的对话：

—How did you do the work?

—It was according to what you told me.

我觉得句中的according to用得不妥，建议改用其他表达，比如：

I did it as you said.

I did it as you told me.

I did it in on your instruction.

I did it according to what you told me.

I did it in accordance with what you told me.