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