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