Here is a tutorial from TOP left to BOTTOM right image:
First take your bag/grocery store (I used doggie disposal bags, or diaper disposal bags would work great too) and I filled it with poly-fil to my desired amount. Next I pushed out some air and tied a small rubber band around the bag. I clipped off the extra un-needed bag. Then I placed the bag in the center of my fabric square, I gathered all corners, tucking were needed and pulled everything to the top center. I again wrapped the pulled fabric in some more rubber bands, and too cut off the extra un-needed fabric. To embellish the fabric pumpkin I then hot glued some ribbon around the pumpkin two pieces connecting from one end to another. Lastly I moved onto the stem. I took some cut green polka dot ribbon and hot glued them from one end to the other. TIP: for the second piece of hot glued ribbon I made sure I tucked in any extra sticking out fabric by pinching it into the first piece of glued ribbon. I finished the pumpkin stem with some rick rack and some jute. You can add your favorite ribbon trims.