You were teaching Ezio your special leap and grab move. It's just jumping high from a ledge and then grabbing another ledge. He was struggling for some time but he managed to get a hang of it and climbed up a rooftop before looking back down at you.

"How's that for my first time?" He asked with his silly little cocky smile, expecting some compliments like he always does. He was trying to impress you so he wants compliments in return. Such a simple man. Venice is a weird and beautiful place.