Caroline extension is a powerful technique to display the final pattern.
As an example, we choose Sardines (Step 7).
(Instead of steps 1 ~ 6 of Sardines, you may do the following steps:
(i) Opening A. (ii) Release thumbs.
(iii) Thumbs move under the near index-finger string and pick up far index-finger strings. (iv) Release index fingers.
(v) Give a 360-degree twist toward you to little-finger loops.
(vi) Thumbs pick up near little-finger strings.)
1. Index fingers pick up far thumb strings with tips and thumbs hold the strings between thumbs and index fingers of both hands.
2. At the same time, extend the pattern.
You may hold the far little-finger string with middle, ring and little fingers.
Steps 1-2 are called "Caroline extension". It requires a little practice.