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