How does Athena get Telemachus to hurry home from Menelaus's estate?

This question is in reference to the events of book 15. It opens late at night, in Sparta, as Telemachus is struggling to fall asleep (at least, this is the suggestion in the Fagles translation). In this situation, Athena stands over him, ready to spur him to depart. She says that in traveling so far from home, he has left his holdings vulnerable, at the hands of those who would "carve up all your wealth, devour it all, / and then your journey here will come to nothing" (The Odyssey, trans. Robert Fagles, Penguin Classics (paperback ed.): New York, 1996, 319). Therefore, she insists that he get Menelaus to let him leave immediately, as Penelope is already being pressured to wed Eurymachus, whose gifts exceed those of any other Suitor.
At the same time, she warns him about the ambush the Suitors have planned against him and gives him instructions for avoiding it. With that, she departs for Olympus. The next morning, Telemachus will again meet with his hosts and, later still, set off on his journey back to Ithaca.