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