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