If you do feel you have a system that can make money and just want to try it out without spending much money there are a few options.
The easiest and cheapest way is to play on a free roulette wheel. It may be cheap but there a couple of problems with this. Play can be slow and if you did win, you wouldn’t get any of this.
You can speed up the play using the turbo mode that some roulette games have. Some games have a handy double up button and handier double up and spin button. This along with the turbo mode means you can play at least 10 spins a minute and probably a lot more. Its still not ideal though as you need to run through thousands of spins to really see the behavior of the system.
If you are confident you could play roulette with small stakes. Sky Vegas have a 1p/ 1c roulette table which you can use to test your systems with smalls stakes.
The best way to test a system though, is to run a simulation. Most people haven’t got the technical skills to do this though. No doubt a good C++ or Java programmer could code a simple/medium complex system up in a few hours. However, for more complex systems and for the average person, using something like Excel or a roulette system designer.
In Excel it is fairly easy to write a few functions which simulate simple roulette systems. For example, use =RANDBETWEEN(0,36) to get the roulette number. Then use an if statement to see if you have won. Say for example you have a bet on red, the chances of winning are 18/37. You can test for a win by saying that =if(RANDBETWEEN(0,36)>18, 1,0)) If you fill a column of these, you can see a sequence of winning bets then.
Excel is fine for simple systems but if you are serious, you need to get a system designer. The one we use is called Roulette Xtreme. Depending on your background this could be really simple or really hard to learn.
Once you have learned how to use Roulette Xtreme, there are many advantages over using a speadsheet, free play or pen and paper to test your systems. With Roulette Extreme, you can simulate, 10, 100, 1000, 1 million plus spins in a click of a button. Your system may work in the short term but being able to see its true long term behavior is better before you put on real money.
You can also use the software to input spins you collected from elsewhere and see if there are any significant biases in the wheel. This is handy if you are trying to use wheel bias to beat the casino. Its unlikely nowadays but you might be lucky and find one you can exploit.
If you are serious about developing a system to make money then using a system designer is the way to go. A spreadsheet might be fine if your system is really simple but its so much easier to us Roulette Xtreme and use that. Find out more at UxSoftware. It costs $30 but its well worth it if you are serious about designing your own system.