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