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