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