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