Don't expect any of the usual betting strategies to help you win in the long run. They all fail sooner rather than later.
The Martingale is probably the best known where you double your bet until you eventually win. Let's look at the
progression: 1-2-4-8-16-32-64-128-256-512-1024 etc. How many people are game enough to go further than
that - if the house allows it. Each 'won' progression only actually wins the value of the FIRST bet - ONE unit.
So you see, it is a very dangerous way to play for very little gain.

I personally used to think The Martingale could help you win until I played RED one night and watched a run of
BLACK numbers which lasted for over 20 spins. Fortunately I lost my nerve a long time before the end of that
run and didn't lose as much as I could have. At least I lost enough to learn a lesson.

Oops, it was the d'alembert (seems to be a number of 'correct' ways to spell it) which I was going to slay the casinos
with. This is the system where you increase by one each time you lose and decrease by one unit each time you win.
You play until you arrive back at your starting unit and then start all over again. It fails in the long term. It killed me in
my experience explained in the previous paragraph about the Martingale. With playing RED and only BLACK showing
for 20+ spins I never reached the 'decrease by one' stage. lol

The Future: Yep, never say die........ :)

Toying around with various strategies which envolve playing two (or three) progressions at the same time.
The theory being that when one progression fails the other(s) win to cover the losses of the losing one and
at some stage reaching a profit whereby I would start again until reaching another profit. I expect my system
to have consistent swings - small losses followed by small gains. It's a system for the even bets of course. It
is also a strategy which doesn't require you to play every spin or even to restrict yourself to one table. You
just need to chart each spin that you actually do play.