When it comes to the mitzvahs we specifically do to draw close to G-d, piety not only comes down to what one is to do but how he is to do it. Those sorts of mitzvahs should be suffused with love and reverence for Him.
(That is not the case when it comes to the mitzvahs touching on our relation to others though. For even when we do someone a favor for the least altruistic reasons and with mind and heart elsewhere, a favor was done nonetheless almost despite us.)
So let us first explore the whole idea of revering G-d, and touch upon loving Him later on.
In order to express true reverence for G-d when they interact with Him, the pious would need to submit to His will, to be humble, and to pay tribute to and honor Him. Needless to say, we’d do well to use their approach as a model of our own interactions with G-d, though we might not achieve all they do.
The main thing would be to revere G-d’s great presence. While praying, for example, or fulfilling any other mitzvah the pious would have to “consider the fact that (they were) literally praying and standing before the King of Kings” as Ramchal words it.
All any one of us would need to come to that, we’re told, would be to seriously and consciously “consider and reflect upon” the fact that “you’re quite literally standing before G-d and are involved in a give-and-take with Him” at every point. In fact, “most anyone can realize that he’s involved in a give-and-take with G-d, that he’s imploring and pleading before G-d Himself, and that G-d is listening to and hearing him” if he’d concentrate enough on it, we’re assured.
But one should not only consider how close he is to G-d, but also how ironically transcendent G-d’s presence is at the very same time. As such, we’d all do well to reflect on “how elevated and above all the blessings and praises of the world and all concepts of perfection one could ever imagine G-d is”, so as to take-in the full scope of His being as best as we can.
Do that, we’re told, and “it would be impossible for your heart to not tremble or be moved when you speak to G-d, or mention His name” in prayer.
But how do we begin to do that? By instigating it in from the outside-in, That is, by going about with your “head bent downward, (and with) a prostrated body, lowered eyes, and with hands folded like a lowly servant before a great master”. That is to say, to assume the right stance beforehand to be in the right frame of mind, and to then await His presence.