You should read the threads on "landing experiences" on this forum. There are several heavily populated threads.
Some people have described each step by counter to counter.
But basically you fill a form while being in the plane near landing, then move to passport control / immigration etc. You should have a list of items you are taking along, indicate financial amount if it is over 10k CAD that you are carrying, plus a list of goods to follow if any.
You should have all basic items like passport (with visa), work permit approval's "Letter of introduction", job offer, contract, LMO and better have contact info of your employer i.e. address and phone number. Who knows they might like to call over for confirmation OR at least ask if you know exactly where you would be going etc.
If going into Quebec, you should also have a CAQ along.