Question

And in my humorous way ,I added (as a trifling jest)' identify the figure of speech

Answer 1

As a trifling jest.
....simile....

Answer 2

The figure of speech used in the above statement is hyperbola, as the statement contains extravagant response.

By conveying a statement in such a way would stress the important fact on the sentence.

That is the reason why what was added was told at first and then how it was made in conveying the sentence is framed.