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