I loved my grammar, I just wish she was still with us. RIP Nanna!
There's supposed to be a technique where on level ground, you place a mark in the middle of the rear of the front tyres (see note), measure the distance between the two marks, then move the car forward (never backwards) so the marks are now on the front face (see note). Then you adjust until it's right.
That won't work with the camber adjustment which is also quite important. For my money, I'd take it to a tyre place and get them to do it.
Total toe-in for an UNLADEN 4WD is 2.2mm (nominal). This is what you get when you subtract the FRONT measurement from the REAR. If the front measurement is larger than the rear, you're way out of adjustment.
Note (for those that need it): If you're looking at the tyre, imagine a clock face placed on the tyre. 12 o'clock is the highest point on the tyre and 6 o'clock is on the road. That means for the LEFT tyre, the front is at 9 o'clock and the rear at 3 o'clock, opposite for the right tyre.