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