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