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