For HSBC, the bank code is 004. You will need to look up your bank code on the internet (this link was useful for me: http://www.sfaa.gov.hk/pdf/common/Form/tsfs/Bank%20Code%20List%20(as%20at%2029.1.2010).pdf )
For the branch code, check your bank statement. It should be the first 3 digits of your full account number.
Your account number will be the middle 6 digits of your bank statement.
To deposit into savings, the last 3 digits for Premier is 888 (PowerVantage is 833). I wanted to deposit into checking, so my last 3 digits was 001.
In total you should have:
3 digit Bank Code
3 digit Branch Code
6 digits for your account number
3 digit account type (001 Checking or 888/833 Savings)