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