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