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