Source 1 : Compact Advanced Student's Book
There is an explanation in the book.
two simultaneous events with the same subject; the participle clause normally comes second
Example:
The woman hurried after her dog, calling to him to come back.
Source 2 : Objective English For Competitive Examinations
When two actions occur at the same time and are done by the same person or thing, we can use a present participle. We can express the first action with a present participle.
Example:
Singing to himself, he walked down the street.
He sang to himself as he walked down the street.
In the first expression, it said "normally comes second".
In the second expression, it said "the first action". Why?
Based on these expressions, can we write this sentence like this?
The woman hurried after her dog, calling to him to come back.
While hurrying after her dog, the woman called to him to come back.
or
Singing to himself, he walked down the street.
He sang to himself , walking down the street.