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