His fighting style revolves around the use of his devil fruit, Jiki Jiki no Mi, which controls magnetism.
Since he starts in Punk Rotten (a giant floating metallic golem). He would go for physical strikes against Sans in this state. But he also has a lot of ranged options. He can just throw metal at Sans with magnetism, shoot metal arrows/bullets at him, entrap Sans in a metallic cage, etc.
With his awakening abilities, Kidd can turn Sans into a magnet, and can turn any object into a magnet. He could also mark two things with S and N, making them always attract to each other, this works on both living beings and non metallic objects. For his strongest techniques he has Damned Punk, a giant laser cannon with a large AoE and range. And Punk Corna Dio, a mecha bull that's even stronger than his Punk Rotten.