Yes, I know backtesting is boring, but it's absolutely critical to measure statistics of your system before you commit any real money to the market.
The only way to make money in the market is to have a system that is profitable over a long period of time. In other words, your system needs to have a statistical probability of success.
Much like a casino, you need to have an edge and then exploit that edge over time to make consistent profits. I can't emphasise the phrase "over time" enough...
Consider the following example, a very simple mechanical system that roughly doubles your capital over a period of one year. Ok, so you're not going to be rushing out to buy that Ferrari just yet, but with compound interest 100% soon becomes 200%, 400%, 800% etc... This system would be ideal for a pension fund, solid steady growth with low risk.
Starting capital $1000, roughly doubles per year (2 years data shown with original capital for analysis, no compounding)
The beauty of backtesting is you can simulate drawdowns that you wouldn't see if you were testing the system in the real world. Look at the chart below, what if you had started to test your system in the middle of May (red area) ? You would think the system was complete garbage and probably abandon it, not realising it was actually profitable over time.
The inverse is also true of course, take a completely garbage system that loses all day long but happen to strike a run of good trades at the start. If you started this one at the beginning of Feb you'd be planning your retirement after one week.
The added bonus to backtesting is you can analyze the results to see if your system can be improved. In the first system with the big drawdown, you can go back and see what the underlying market was doing at the time. Was the market ranging for a long time and your system suits a trending market instead ? Was there a stormy period in world finances that meant you should have stayed out the market during that period or switched to a more suitable system for those conditions ?
Backtesting a system doesn't guarantee by any means that your system will be profitable in the future, but testing it on historical data, a lot of historical data, will give you the best information possible before risking real money.
Disclaimer : If you blindly act on the advice of strangers from the internet then you're an idiot and probably deserve to lose all your money. There's no fast track to success. Do your own research and make informed decisions based on all available evidence. Critical thinking is the key to everything.