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