Hmmm, that's odd, never heard anybody tell me something like this before.

The main point is to just NOTICE your breath. No need to change anything. Can you just notice that you're breathing? It's just a shift in your attention. Away from the monkey-mind through stream into the present moment. It produces magical results. But be forewarned, that monkey-mind wants your attention 24x7 and doesn't give up easily.

If on the other hand you wanted to practice deeper breathing, which is a great exercise because 99% of the adult population are shallow breathers, you should always start by performing an exhale where you slowly, evenly push out all the DEAD AIR out of your lungs. When you do the exercise it will feel like you're pulling back your stomach as the last of the dead air is finally forced out. Anyway, once there's no more air to push out you'll take a complete and perfect FULL BREATH, perhaps for the first time in decades. And the following couple of breaths will be mostly full as well as you gradually slip back into your habitual shallow breathing patterns.

So net-net, always start the full-breath exercise with the full exhale first. And the noticing exercise is a 100% ZERO EFFORT practice. All you're doing is shifting your attention.

Good luck!