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