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