1. Place your slip knot on a needle. Hold the needle in your right hand pointing to the left. Hold the slip knot in place with your right index finger so it does not fly off the needle.
2. Place your left thumb and index finger in between the two strands of yarn dangling from the needle. (Your thumb should be closer to you and the index finger away from you.) Hold the dangling yarn taut with your ring and pinky fingers.
3. Flip your left thumb up while guiding the needle down and to the left. A loop should form around your thumb.
4. Guide the needle up through the loop on your thumb
5. Guide the needle over the yarn that is around your index finger and catch it with the needle.
6. Guide the yarn hooked by the needle down through the loop around your thumb.
7. Slip your thumb out of its loop and place this thumb inside the strand of yarn that is closer to you. Pull down gently and you have a cast on stitch!