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