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