"because i could not stop for death "
what has the speaker done to prepare for death?

They have gone on a long ride with the personification of death through what could be assumed as either the speakers past life experiences or the joys of life. This review prepares the speaker for death because they become comfortable with what they'll be taking into the afterlife. They've also become comfortable with Death, their companion throughout the poem.

Explanation:

boccaccio employs the voice of his narrator dioneo to represent his ideas on the tension between masculinity and femininity.  while dioneo excites the members of the brigata and recognizes women for their unique skills and independent ideas, he concludes the decameron with a story reminiscent of the society from which these young aristocrats escaped, revealing misogynistic overtones.  dioneo boccaccio is able to explore the gender disparity which is inherent in 14th century florentine society.