What will he burn, and what will he plunder?
Radak #1: He will burn the houses in which Egypt's gods are, and plunder the gods of silver and of gold.
Radak #2: He will burn the houses in which Egypt's gods are, and take captive those who serve them.
What is the comparison to a shepherd?
Rashi: Nebuchadnetzar will wrap all the spoils of Egypt and leave, like a shepherd rolls his garment and casts it over his shoulders when he brings the flock in front of him.
Radak: He will take all the spoils of Egypt like a shepherd wraps himself in his garment. It mentions a shepherd, for he stands day and night in the Midbar with the flock, and he wraps himself tightly in it due to the cold at night.
Radak citing his father: A shepherd travels from place to place. When he leaves, he wraps the cloth of the tent he dwells in, and goes. He does not leave anything there.