How to protect our trading strategy?
The bottom line and short answer is, you can't really. Unless you are using family members or extra loyal friends, the chance that the trader takes it to somewhere else and trade your strategy there will always exist.
The reverse strategy as was advised above also doesn't work, because as long as a system is consistent (loser or winner) it can be used as a winning system.
Look at it this way: As long as your system isn't affected by more people using it, like liquidity issues, others using it might actually strengthen the system. You bought long? Well, so did others thus pushing the price in the wanted direction.
So I would say, don't worry about it, unless it is such a fragile system that competition would kill it, but then you might need a better system...