Iron setting - Wool and Steam (irons vary - you may need to set yours higher or lower to find the proper fusing temperature.)
Effect of heat and pressure squeezes softened resins into fashion fabric.
Cooling time is as important as fusing time - Let cool completely before handling.
Use downward pressure for 10-15 seconds each position. Do not glide iron back and forth, but lift and press.
Some moisture is needed, never soaking wet. Press cloth dampened or misted only.
Record and file your test results - even the rejects - for future reference.