Its pretty simple. Drop your tabs into cold water and wait/stir to dissolve. Once the tablets are completely broken down, filter the mixture using a coffee filter or fine weave fabric. The solution you end up with should be fairly free of white sludge (the sludge is the paracetamol and tablet fillers etc). Discard the filter and sludge and drink the clear(ish) solution which will have the codeine dissolved in it.
For future reference, the reason that you didn't have thousands of people jumping to help you is that this topics has been covered over 9000 times on BL - a simple search would have given you multiple threads to read. Good luck!