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)(28,35)(29,31)(30,32)(34,37)(36,39)(38,40) involution — undirected(1,2,4,5)(3,6,7,8)(25,27)(26,28)(29,34)(30,35)(31,36)(32,33)(37,40)(38,39)(10,15)(11,16)(17,22)(18,23)(25,26,30,32)(27,33,35,28)(29,31,38,40)(34,37,39,36)(1,3,4,7)(2,6,5,8)(9,11,14,16)(10,12,15,20)(13,18,21,23)(17,19,22,24)(25,26)(27,28)(29,31)(30,32)(33,35)(34,36)(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)(31,39)(32,35)(34,40)(36,38) involution — undirected(9,13,14,21)(10,17,15,22)(11,18,16,23)(12,19,20,24)(25,29,30,38)(26,31,32,40)(27,34,35,39)(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.