When you crochet a small round piece, like a spot for a giraffe or dinosaur, you should avoid a visible knot when you fasten off your piece. You can use invisible finish to make sure the piece is perfectly round, with no visible knot, or the following technique also works well:
1. Finish the last stitch in your piece and cut the yarn (leaving a long tail for sewing)
2. Slip stitch into the next stitch
3. Pull the hoop to make a larger hoop
4. Remove your hook and put it through the next stitch from back to front
5. Grab the hoop at the front and pull through the stitch, so it’s now at the back of the piece
6. Pull the tail end (the long piece you left for sewing) through the hoop
7. Gently pull it all the way through until the hoop gets smaller and fastens
8. You should now have a perfectly round piece without a visible knot (or knobbly bit)
Little Green Bear 