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