I have four separate bank accounts for different purpose:
1 - For living expenses and GIRO
2 - For Emergency Fund (3 months in conjunction with FD period 6/12 months)
3 - For Investment and Trading
4 - Fixed Deposit (Mid Term Saving)
With the 4 bank accounts, I am absolutely clear on money movement and transactions. It also helps to save time (less than 5 mins) in tracking by just downloading the monthly statement from the each bank.
I also simplify it into broad category as follows:
I have another diary to record big ticket items following Pareto Principle - 80% of your expenses are from 20% of big ticket items and don't sweat on the 80% of the items that contribute only 20% of expenses.