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