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