Once you get used to the technique, you'll be able to do it without closing your eyes, nor touching your hand to your heart centre. What the technique does is, it calms us, soothes us, & when this happens we can make better choices. Heart Math has it's basic technique then the next step from this technique is to ask yourself, at the heart level, what is the best decision to make, or the best course of action, in a situation (which is causing us problems). So, using the intelligence of the heart. It is said, that 'the heart doesn't lie'. But, we become disconnected from this, & this lovely technique will bring us back.
Close your eyes, put a hand over your heart centre. This is on the centre of the chest, &, interestingly, is where people often put their hand when asked to put the hand on the heart. The physical heart is slightly to the left of the heart centre. The heart centre is the trigger point for the actual chakra which is in the spine. If this doesn't suit you, put your hand on your heart. No worries, just do what feels best to you.
Become aware of your breath, however it is: fast, slow, erratic, whatever. Observe it & allow it to slow down. Start repeating a mantra with the breath: in = So; out = Ham. So-ham. Relax, soften, on each exhale. Imagine that the breath is flowing into the heart centre (or heart), & out of the heart centre. Do this till you are calm...it won't take long, anywhere from 30 seconds to maybe a couple of minutes. When this is completed, with eyes still closed, look up to the eyebrow centre (between the eyebrows & slightly above, where Hindus often wear a red dot, not between the actual eyebrows), & at the eyebrow centre, visualise a small golden flame. The flame is completely still. Hold this image for a short while, then release it, & notice what your emotional & mental states are like.
You could do this as an actual meditation, morning, &/or evening (especially after a hard day).
Be warned....... whatever is bothering you will really show up as you connect more & more to the wisdom of the heart. By dealing with your problems, using the intelligence of the heart, you will be also dealing with daily karmic 'lessons'. Your heart will tell you what to do. And, you will be fulfilling your dharma, or life-path for this lifetime.
Using either the heart, or trigger point for the heart chakra (anahata chakra) is more effective than charging in & trying to use the actual heart chakra. This is a very High chakra, we need guidance to get there. And, with all the weird concepts & non-knowledge that goes around to do with the chakras, in particular the heart chakra, it's best to start with the trigger points.