Quote from Jason Rogers:
Our research team at DailyFX.com did a study recently on profitability by looking at the results of tens of thousands of traders. They found that traders should look to use an effective leverage of 10-to-1 or less. That means with $5000 in your account, your total trade size should not exceed $50,000.
I agree. I started following that 10 to 1 rule when I opened the Questrade account. I have been profitable ever since.
3 to 1 is available in my margin account for stock trading, but I rarely go above 1.7 to 1.