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)(11,15)(12,14)(13,20)(16,21)(17,18)(19,24)(22,23)(25,26,31,35)(27,36,39,32)(28,33,40,30)(29,37,38,34)(1,3,5,8)(2,6,4,7)(9,11,14,17)(10,15,12,18)(13,19,21,23)(16,22,20,24)(25,27)(26,32)(28,37)(29,33)(30,38)(31,39)(34,40)(35,36)(10,12)(11,17)(16,20)(19,23)(25,28,31,40)(26,30,35,33)(27,37,39,34)(29,32,38,36)(9,11)(10,15)(12,18)(13,19)(14,17)(16,22)(20,24)(21,23)(25,28)(26,33)(27,37)(29,32)(30,35)(31,40)(34,39)(36,38) involution — undirected(1,2,5,4)(3,6,8,7)(9,12,14,10)(11,18,17,15)(13,20,21,16)(19,24,23,22)(25,29,31,38)(26,34,35,37)(27,33,39,30)(28,32,40,36)(1,4,5,2)(3,7,8,6)(9,13)(10,16)(11,19)(12,20)(14,21)(15,22)(17,23)(18,24)(25,30,31,33)(26,28,35,40)(27,38,39,29)(32,37,36,34)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.