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