A picture of that area, with the mat under your brake pedal, might answer lots of questions we may have.
I recommend you install the rear half of carpet, first, and overlay the front on top of the rear (where they overlap)
If you have a reference point for the high beam switch in the carpet, I recommend you work from that. Once the carpet is anchored (more or less) at the high beam switch, laying the carpet across over the hump to the passenger side, keeping it even, it will become clear and intuitive where the placement should be.
Because these carpet kits are aftermarket, the precise placement of the mat area will vary. But my intuition is the mat is centered, left-to-right, in the driver side well where the feet go. Forward to back placement will depend where the carpet falls after you set it on the high-beam switch.