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