For my projects today I am using my large EasyPress. When it comes to applying heat you want to follow the time, temperature, and pressure settings for your HTV material.
With each fabric, you will need to pre-press the area you're applying the HTV to. This will remove any wrinkles and any moisture that is in the fabric.
After pre-pressing I like to go over the area with a lint roller to make sure there is no hair, dust, lint, etc on the fabric. Having things between the fabric and the adhesive can create a less-than-desirable finished product.
When your shirt is prepped locate the bottom layer of HTV onto the fabric.
Cricut SportFlex Iron-on has a time and temp setting of 305° for 30 seconds. It also calls for firm pressure. You'll need to apply firm pressure the entire time.
I added an EasyPress mat inside my shirt and then pressed the first layer for about half the time.
SportFlex is a cool peel product. You need to allow the carrier sheet to cool completely before trying to remove it.
You'll want to start at the corner and peel it back slowly making sure the HTV is stuck down on the shirt.
If you notice any lifting, lay the carrier sheet back down and press again. Allow to cool and remove the carrier sheet.
Save your carrier sheet, we'll need it when applying the top layer.