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