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