One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,8)(6,7)(9,10)(11,15)(12,19)(13,14)(16,20)(17,21)(18,24)(22,23)(25,26,31,37)(27,36,30,32)(28,34,39,33)(29,35,40,38)(1,2)(3,6)(4,7)(5,8)(11,17)(15,21)(18,23)(22,24)(25,27,31,30)(26,32,37,36)(28,35,39,38)(29,33,40,34)(1,2,5,8)(3,4,7,6)(10,14)(15,21)(16,19)(22,24)(25,28,31,39)(26,33,37,34)(27,35,30,38)(29,32,40,36)(1,3)(2,6)(4,8)(5,7)(9,10)(11,15)(12,16)(13,14)(17,21)(18,22)(19,20)(23,24)(25,28)(26,34)(27,35)(29,32)(30,38)(31,39)(33,37)(36,40) involution — undirected(1,3)(2,4)(5,7)(6,8)(9,11,13,17)(10,15,14,21)(12,18,20,23)(16,22,19,24)(25,29)(26,35)(27,34)(28,32)(30,33)(31,40)(36,39)(37,38)(1,4)(2,7)(3,8)(5,6)(9,12,13,20)(10,16,14,19)(11,18,17,23)(15,22,21,24)(25,30,31,27)(26,36,37,32)(28,38,39,35)(29,34,40,33)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.