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