My once a week shoulder routine (actually i do delts+tris):

Military press or Db presses (i switch each 1 or 2 weeks). 4 x 15, 10, 6, 4
Lateral raises 4x 15, 12, 10, 8
Front raises 3 x 12, 10, 8
Shrugs 4 x 15, 12, 10, 8