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