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