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