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