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