After you have removed the excess puffy foam after sewing a design, you may notice little bit and pieces still poking out between the threads, as shown below.
If you don’t have a “heat gun”, you can always use a hair dryer, iron or other heat generating implement to melt the excess away. The key is not to get too close and scorch the embroidery. Start with your implement at a reasonable distance from the design and gradually move in closer until the puffy foam hairs start disappearing. The result will be crisp, clean embroidery using foam as seen in the after pic below.