Speak to Researcher Aillena Belzia at 1176, 12, 1281 in the Tranquil Sea to begin this quest.
Leave Sapswill through the gate at 1261, 14 1068
Follow the dirt path, clicking white sparkles on the right-hand side along the way to mark it. They're not very far apart, so if there's a long gap backtrack and look at the grass carefully for the sparkles.
Find Digmaster Hidswinn: he's at 1105, 41, 1060
Go up the hill to 1147, 75, 938 and set off the flare (click on the light)