Being arrested and charged is a very scary and stressful thing. Whether it is for impaired driving, assault, possession of weapons, or any other offences the first thing you need to do is get some legal advice before talking to the police. You should be polite and answer any questions concerning your name and address, etc.. The police are required to give you an opportunity to call a lawyer. Always take them up on that offer and always follow the instructions your lawyer gives you. Whatever you say to the police can be used against you. You may be helping them to make a case against you without actually realizing it. The best advice is to say your lawyer has instructed you not to make a statement or answer any questions, if that is indeed the advice you are given.
When the police complete their interrogation or their interview, they may decide to release you with certain conditions. It is best to accept those conditions as they could be varied later by your lawyer if necessary. Or the police may be opposed to your release and want to detain you. You will need to advise your lawyer of this development and he/she will represent you at a bail application that day possibly, but more likely later in a courtroom the following day.
In Canada, a lawyer is not allowed to be present during a police interview or interrogation, so it is even more important that you contact a qualified criminal lawyer and follow their advice. It is essential that you adhere to the conditions of bail, and if required attend all court hearings and be present for your trial.