i thought it was common knowledge as to how you clean your boots? Water is just to get the initial dirt off.
What i do after every use is this:
Take one of those finger nail scrubbers (or any stiffer brush that you have that you can put under water, and isnt stiff enough to damage the leather), run it under the tap then scrub the boots to get the dirt off. Maybe take a wet cloth to it if it's needed to get the loose dirt off. Then dry with another cloth.
Now the treatment.
After cleaning i spread and work in mink oil with a cloth. Vaseline works as well, anything that will protect and keep the leather soft.
Repeat after every use and you shouldn't have any problems.
If you lose the white colour, it's cause you arn't doing this and leaving the dirt on. I guess if its left on and put through the elements with old dirt on then its gonna stain the leather, so dont do that.
I've got the Silver Beckham Pulses on their way, and they're gonna be shining from start to finish. Show your boots some respect and they'll treat you well.
-edit- the only time i've used coloured polish is when i've damaged the leather, and even then it's a waste of time because it only helps in the moment. It'll come right off in practice or game.
BTW - Mink oil and vaseline are clear.