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