I have had a great deal of long term success using the following progression with various selection methods for double columns:

2:2:1:2:2:3:4:5.....

I have used this "dip" progression mostly applied to either 2 columns or 4 x 6-line (for some reason I have always preferred these to the dozens?)

With any sensible selection + wait for right opportunity you should get the first two wins regularly. The third "dip" bet locks in a profit for the series.

Increase the bet?

Normally I have operated on the basis of stopping at 10 units profit for the first 3 attempts(even if the progression is continuing to win I stop and take the profit)

After this I will follow the progression until it breaks -capped at 5 units. And if very successful I will extend it thro' to 10 units.

As with any positive progression you are fighting against repetitive small losses waiting for a win when the progression bites. To overcome this I have used combined strategies - recording each of them and moving between them if one repeatedly breaks down - and occasionally using increased bets to recover initial losses.
One of the mildest of these is to change to 3:2:1:2:2:3:4:5

Hope this is of use to you to work on. It can be made to consistently win.