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