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