Toss the apple in lemon juice in a bowl if making ahead.
Using a 7-inch bamboo skewer, spear a green grape, an apple slice, a slice of celery, a green grape, and a group of 3 three salad leaves—a baby gem, a baby spinach and a piece of frisee, pierced through the middle onto the skewer.
Repeat with an apple slice, a celery slice, a green grape and three salad leaves. Add a third apple slice, a third celery slice and fourth grape. Repeat the process to build three more skewers.