Pinning down "double roulette rules" is done at the wheel. Roulette looks like pure chance, and it is, but the rules still decide how much any bet costs. A European wheel has one green zero, an American wheel adds a second, and French tables add rules that return half of some losing bets. Knowing which wheel is in play, what each bet pays and what the zero takes is most of what there is to know about playing roulette sensibly.
Licensed roulette wheels are not rigged: they are tested and balanced, and casinos log results so that a biased wheel would show up in the numbers. Balls are not weighted; they are made to a standard size and material, and a worn wheel is replaced rather than exploited. Roulette machines use a random number generator that is checked in the same way and cannot be fixed by the casino. Under licensing regulations there are no illegal bets on the layout itself, although devices that try to predict the ball are banned nearly everywhere.
Roulette odds come straight from the wheel. On a European wheel there are thirty seven pockets, so the chance of landing on green is one in thirty seven, and on a double zero wheel one in thirty eight. Red and black each hold eighteen pockets, and neither color wins more often over time; a streak of one color says nothing about the next spin. The color rules are simple: zero counts as neither red nor black, so even money bets lose when it lands.
Each spin charges the same share of the stake, so a live table at about forty spins an hour drains a budget far slower than a fast online game.
Call bets are placed by name on French layouts; the neighbours bet covers a chosen number plus the two pockets either side of it on the wheel.
When zero lands, la partage gives back half of any even money stake, so each of those outside chances costs the player half what it would on an ordinary single zero table.
Neither: each colour holds eighteen pockets, streaks say nothing about the next spin, and zero counts as neither, so even money bets lose on it.
Choosing a single zero wheel, holding to a fixed budget and knowing when to stop is the only approach that works, since the edge stays constant.
A European wheel has a single green zero, an American wheel adds a double zero, and French tables use the single zero with rules returning half some losing bets.