From The Heavenly Counsellor in Isaiah xl 13-14: A Study of the Sources of the Theology of Deutero-Isaiah (Society for Old Testament Study Monographs):

We therefore suggest that the content of the supposed knowledge taught to Yahweh in these verses is the practical knowledge required to create the world; and we translate them as follows:

Who has understood the mind of Yahweh,
or who was his counsellor, who instructed him?
Whom did he consult for his guidance,
and who taught him the way to achieve order,
And showed him how to exercise creative skill?