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