step 1:
draw a triangle with rounded tips on the cardboard to make your ear stencil. then use it to cut two triangles from the foam

Step 2:

then line up the foam on top of the fabrics and cut large squares out of them

now put the colour for the inner ear on the foam and glue edges in place. cut all excess

stretch the outer ear fabric to slightly cover two of the ear sides and glue those in place

mark about an inch and 1/4 from the seam down the center of your hoodie and about 2 1/2 inches back from the front and glue each ears witht the innner end 1 1/4 inches away from the center seam. and ur done