A device and technique for knotting an inflated balloon or forming a knot in another material is provided. One approach includes: holding a knot tying aid by a handle portion, the handle portion being positioned opposite a distal portion, the distal portion including several prongs (in one nonlimiting example at least three) extending away from the handle and being spaced apart from one another in correspondence to vertices of a triangle; winding a tag end portion of the inflated balloon about the prongs to form a loop; and passing part of the tag end portion through the loop to form a knot.