The purpose of a short-field takeoff is to get off the ground at the best angle of climb (VX)to clear an obstacle. Make sure you know and use the best angle of climb airspeed and attitude as recommended by the manufacturer.
The most practical way to perform a short-field takeoff is to set the brakes, run the engine up to nearly full throttle, then release the brakes to minimize ground roll. Some aircraft manufacturers suggest applying 10-degrees of flaps first; check the owner’s manual for recommendations.
Your instructor will have you practice these procedures many times before releasing you for the practical test (checkride). That’s good. If you ever face an emergency where you have to take off on a short with crosswinds you’ll be glad you practiced, practiced, and practiced some more!
One of my most exciting moments of flying was performing a short-field takeoff from a 1,300-ft. runway with obstacles (trees) at the end, and realizing at the halfway point that I hadn’t retracted the flaps after the prior landing. Fortunately, I buzzed a couple of the shorter trees without contact. Most important, I learned a very valuable lesson about pretakeoff checklists!
"Man cannot discover new oceans unless he has the courage to lose sight of the shore."
-- Andre Gide