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