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