The most basic thing to do is just let them observe you while talking them through what you are doing and why you are doing them. It is possible to tell them when to upshift or downshift while you are driving. This should give them an outline of what they would have to do when they are behind the wheel. Making them comfortable behind the wheel should be what you have to accomplish. The more technical things should be taught by a professional driving teacher which is why it is crucial to have them go through driving school.
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