Rav Amram Gaon Method:
This method defines a chulyah as a group of three twists. It has 13 chulyot, and alternates white and Tekhelet between them, starting and ending with a chulyah of white. Though Rav Amram Gaon does not mention any knot at the begged, most people do in fact tie one there.
Gaonika Pg 331
This is the length (order) after the bottom knot [the knot closest to the garment]: One Chulya [i.e., a group of 3 twists] of white strings, then one [chulya] of tekhelet, then a chulya of white, then a chulya of tekhelet, then one of white, then one of tekhelet, then one of white, and then the upper knot in tied. And this is the meaning of “one should not have less than seven”. And if one wishes to have thirteen, he continues according to this order.
גאוניקה עמ’ 331
כך היה גודל לאחר קשר התחתון חוליה אחת של לבן ועליה של תכלת וחוליה של לבן ועליה חוליה של תכלת ועליה חוליה של לבן ועליה של תכלת ועליה של לבן וקושר קשר העליון וזה הוא לא יפחות משבע ואם רצה להוסיף עד י”ג מוסיף כסדר הזה
- A “Single Cord Knot” is made by taking one strand of the total eight, wrapping it once around the remaining seven strands and tucking in the end in the wrap.
- A white “Chulya” is made by taking one white strand from the total of eight strands and wrapping it around the remaining seven strands three times. This “wrapping” strand is designated “Shamash” and is used for all subsequent white chulyot (though it is not halachically imperative that the same Shamash be used).
- A blue “Chulya” is made the same as a white one, but just using a blue strand.