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