After printing is complete, the ink needs to be heat set for wash-ability. You can use a conveyor dryer (screen print dryer) or a heat press. Nearly all decorators use the heat press as they can place it right by the printer. Cure times vary, but most manufacturers recommend about 330 F for the curing temperature.
When using a heat press to dry pretreat, use heavy pressure for about 20-30 seconds until the shirt is dry. You cannot print on a damp shirt without ill effect. When curing a printed shirt, you will use light pressure so as not to mix the white and color ink together for a dull finish.
You want to use a silicone-coated parchment paper to protect the heating element from a buildup on pretreat or ink. You don’t want to use the Teflon sheet that came with your heat press. Teflon holds in the moisture, which impacts your ability to cure a water-based ink.
-Terry Combs, Equipment Zone
Read about Determining Costs of DTG.