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