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