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