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