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