There are a few ways you COULD do it... I would load up another hair model that has bangs like what you want to add, say Kozaburo's morph hair, open the group tool, make a new group with the "bangs" material group, and spawn a new prop of just that... then tweak it until it looks like it goes with the ponytail, then parent it either to the head of the figure, or to the ponytail... or if you want a more permanent option, export the bangs and ponytail as a new .obj file and reimport it... just make sure you know which parts have what material settings, and which texture map goes to each part... Hope that was helpful.