Well, I have both wheels memorized, isn't that hard, and you'd bet in sections, just split the wheel into 4 sections, betting 9-10 numbers for each section.
As for the practice, you'd be amazed how well you can pick up 'beat frequencies' if you have the talent for it.
I am prior Air Force and some of us could listen and tell you what jet/plane was flying based on the beat frequency (constructive destructive interference from soundwaves coming off the engines/props). For me and a few others, it was easy, for most people, they just can't hear the difference.
There would/could be sometihng similar with the roulette wheel. When the ball spins it has a certain noise with its velocity. You can 'hear' when it is slowing down. Match this up with the 'rate' the wheel is counterspinning and eventually you will be able to tell 'when' the ball will hit and in what section. But like I said, it would take some practice. Other factors involve the wheel in question. The more expensive wheels spin really really smooth (which is what you'd want, less variables). Also, the ball density comes into play. The heavier balls tend to 'stick' while the lighter balls bounce all over the place.
Lastly, their is the dealer. Some dealers spin the hell out of the ball and then wave off all bets relatively shortly after the spin. Other dealers are a little more lax, spin, and give you almost all the way until the ball drops before they wave you off.
Even with all this, the little metal barbs within the wheel add another variable of randomness, they may the ball drop immediately or skip a little bit further. But even still, I think with the above you could significantly reduce the variance such that you have a mathematical edge over the house.
In fact, this is making me want to buy a roulette wheel and practice
Holy shtt, just looked on ebay, roulette wheels are around $200 - $700.
I might actually give this a try next year, LOL, of course, if I make it work, I can't tell you about it