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