Thank you for your question. Most commonly the gate is located in the middle of the foot (sole), facing downward toward the Earth. There can be a great deal of variation among different humans as to its exact location. For many it is more toward the toes, a bit more toward the ball of the foot.
As for feeling it, this is a question about sensing qi, which is difficult to do without in person coaching. Generally, if you move the palm of your fully opened hand along the bottom of the foot, you may feel an area of greater density, temperature change, or an electricity-like sensation. This is an indicator of the gate. More likely, as you work to pluck the gate, you will actually feel the gate being plucked and/or the act of plucking. This sensation can be immediate or take several years. Most people require a few months, but you should allow the sensation to develop naturally rather than adhere to an artificial timetable.
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