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