Minimize surcharges, look at UA SK LX TK CA MS SQ SA.
Be self-sufficient on IFE, even bring a few more snacks/water
Avoid overnight flights, if possible. If not (such as the case with most e/b TATL, and SA flights), learn how to sleep sitting upright on a plane, prepare in advance (be tired my departure time, try to give a some recovery time upon landing/transit by taking advantage of 24-hr transits), and hope for a row of three/four seats to be empty.