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