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