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