Instead of just numbers, let's use a more descriptive approach:
Think of the engine as facing you.
* Passenger side (Right): Cylinders 1, 3, 5
* Driver side (Left): Cylinders 2, 4, 6, 8
The firing order (the sequence in which the cylinders ignite) is typically 1-5-4-8-6-3-7-2. Using this firing order and the above side designations helps determine the relative location within each bank. There is no single "number location" as they are arranged in a V and each bank is offset from the other. You need a diagram or the engine itself to visually confirm the exact position of each cylinder.