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