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