Question about a homemade linear potentiometer

I'm trying to make a homemade linear potentiometer, but quite new to it. Does anyone have some advice about that? I have already the copper could be the wiper, is there any suggestion about material for the resistive strip? I tend to use this homemade linear potentiometer to controls the brightness of LEDs.

I have a quite close deadline for that... Any help would be appreciated.

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A resistive strip is easily made using a #2 pencil and a strip of paper.

Paul