In reality, the entire process of opening up the clay and forming the base should only take a few seconds. As for the wheel speed, it's often asked, and I typically spin quite quickly—not full speed but fast. The reason I've shown you various techniques at the end is to demonstrate that there are multiple hand positions and methods for opening up the clay, tailored to different types of pots. This technique is just the one I use, and I hope you can find something that works for you.
The goal is to make this process of opening up the clay feel comfortable. If you find that holding your hands in a certain way is painful or awkward, like it is for me when I use two thumbs to open up, experiment and try other techniques until you find something that fits you. This is the joy of throwing pots on the wheel; no two potters do it exactly the same way. Our hands, arms, shoulders—everything used in this process—differ from person to person, making this craft unique and personal.