you sit down at the roulette table. and chart. the first column if the number i.4.7.10. plays. and the two numbers in the same street have not shown you start betting this street. you do the same with the second dozen. and the third dozen you are now playing three streets. let me know how you go. good luck.
i think this is a better way to play this. any number that hits in the first column you play a six line. if 19 hits you play 19to 24. till it wins. and move on to the next number to play in the first column. i have had very good results playing this.