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