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