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