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