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