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