All of the above, but i wouldn't recommend pushing the macroline in before pressing the collar, i've seen a few fittings jam this way.
You need a bit of play in the macroline, and keep the bends as large and smooth as possible, and the macroline should go into the fitting in a straight line, not angled.
If the macroline goes in at an angle, it will burr up inside, and you'll have trouble removing it, and it may leak.