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