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