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