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