One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,5,7,8)(9,10)(11,16)(12,18)(13,20)(14,19)(15,17)(21,24)(22,23)(25,26,31,36)(27,33,28,32)(29,38,39,34)(30,35,40,37)(3,7)(5,8)(9,11)(10,16)(12,14)(13,17)(15,20)(18,19)(21,22)(23,24)(25,27,31,28)(26,32,36,33)(29,35,39,37)(30,34,40,38)(1,2)(3,5)(4,6)(7,8)(10,17)(11,20)(14,21)(18,23)(25,28,31,27)(26,33,36,32)(29,35,39,37)(30,34,40,38)(1,3)(2,5)(4,7)(6,8)(9,12)(10,18)(11,21)(13,19)(14,20)(15,22)(16,24)(17,23)(25,29)(26,34)(27,37)(28,35)(30,32)(31,39)(33,40)(36,38) involution — undirected(1,2)(3,5)(4,6)(7,8)(9,13)(10,11)(12,19)(14,23)(15,16)(17,20)(18,21)(22,24)(25,29)(26,34)(27,37)(28,35)(30,32)(31,39)(33,40)(36,38) involution — undirected(9,14,15,21)(10,19,17,24)(11,12,20,22)(13,23,16,18)(25,30,31,40)(26,35,36,37)(27,34,28,38)(29,32,39,33)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.