To make money playing roulette, correctly guess the number or type of number the ball will land on when the dealer spins the wheel. In a roulette round, play starts after the dealer clears the table of the previous game. At this time, place your bets on your desired number slots.

Seriously: roulette is random, every number has equal chance of winning. From pure probability theory you can calculate what is the probability of winning, no luck involved. I define "luck" as the difference between average expected results to actual results. In the long run it's zero.

Trading the Betfair markets is most definitely a genuine earning opportunity and for those who are determined and committed enough, it certainly can and does replace a full time job. And then some.

Yes you can make money laying horses on Betfair but it is not as easy as you think many punters wander into this with the understanding you have typically N-1 runners in horse race on your side where N is the number of horses in the race and 1 is the horse you have layed to lose the race.