The next emotional key to successful trading is to be able to handle the Money.
Look at a systems average loss. Can you take that loss? Can you take that loss on roughly half of every trade you make?
One thing to do is to look at the historical performance and fund the account accordingly. A trader might not want to risk more than 1% of a $50,000 per trade. As such, the trader should only trade systems whose average loss is less than $500.