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