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