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