2 shades of green felt
Yellow felt for stomach and eyes
White felt for mouth (not pictured)
Black felt for backing
Needle and matching or contrasting thread
Safety pin or pin back
Obvious first step would be to cut out your pieces. I used a needle and green thread to add details.
Next, begin gluing down your pieces in this order:
1. Eyes and belly to frog body
2. Arms slightly overlapping frog belly
3. Mouth covering top of arms and bottom of eyes
4. Lily pad to black felt
5. Frog to lily pad and black felt
Finally, trim off the excess black felt and glue your pin to the back.
Here's the finished pin, from inspiration to fruition!