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