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