Just do it the high tech way by using Cardiac Coherence apps like Inner Balance. Scientists studying Heart Rate Variablity (HRV) looked at all the highly skilled groups of mediators in the world and found basically the same thing - they all breathe at their resonance frequency and that puts their HRV in synch with their breathing and spectral analysis shows a pattern of electrical activity in the heart with a very narrow band around 0.1 hertz.

Cardiac Coherence apps basically hook you up to a sensor capable of detecting this and then allow you to pace your breathing at your resonance frequency to enter a state of cardiac coherence. Apparently it works wonders.

I'm going to take it up very soon.