The Mona Lisa is probably the most famous painting on earth.  What was in Leonardo Da Vinci's heart when he painted the Mona Lisa?  The answer is - nobody knows.  And nobody will know.  You can't know what was in Leonardo Da Vinci's heart unless you were in his presence while he painted it.  And even if you were - you'd need to know him, and be able to converse freely with him while he was painting it.  If we want to grab ahold of God's heart, we have to be in His presence, and to know Him intimately.  I always want to be living in God's presence.
 
The Lord has laid on my heart recently, a deeper desire to live always in His presence, having a constant intimate connection with Him.
 
The more we are in His presence, the more we will know His heart as He works through all the 'painting' He is doing, and allowing in our life.  Imagine Leonardo Da Vinci had his child (his son or daughter) with him while he was painting the Mona Lisa.  I don't think that child would be too concerned about what the painting looked like - outwardly beautiful or not.  He or she would just be happy to be with Daddy.  The funny thing is, we will actually be concerned less with what His 'painting' looks like for us (hard circumstances of pain, highs and lows of life), because we will have the greater blessing that we are WITH the Lord Himself - if we really love Him.  The beauty of Christ, and God - those are the greatest blessing.  We will be chasing after His presence - not His gifts.
 
One instance in the Bible which has helped to give me a lot of clarity of what being in God’s presence does NOT mean, is the example of Peter during the transfiguration.  Peter was so taken up with the 'mountaintop' experience, that he did not appreciate the simple presence of 'ordinary' Jesus alone in 'ordinary' circumstances (after the transfiguration had ended).  And God's response to Him was 'LISTEN' (Matt 17:5).   I suppose that seeing Jesus alone, as normal, after that whole experience felt a bit under-whelming (Matt 17:8) to Peter.  Most of life is like that - ordinary.  But that's where we have to learn to live in God's presence.  Life does not consist of mountaintop, blissful glorious, exciting experiences. If that’s what we’re after, then we’re not after God Himself, really.  We're not after a state of blissful excitement - That's a counterfeit of God's presence.  Emotional highs are not God's presence, and that is proved because just like the transfiguration - no emotional high lasts forever.  We want to live in God's presence in reality, which means in the day-to-day tired, long, trial-filled messes of life.  "Though I walk through the valley of the shadow of death, I fear no evil, for you are with me".
 
So how do we get into God's presence, everyday?  This one verse is the most clear verse I know that shows me the way, the secret to it:
 
John 14:23 "Jesus answered and said to him, "If anyone loves Me, he will keep My word; and My Father will love him, and We will come to him and make Our abode with him."
 
"In God's will is in God's presence"
 
He makes His 'abode' (home) with us when we keep His Word.
 
In God's will is in God's presence. And in God's presence is fullness of joy - Psalm 16:11.
 
Just like how two strangers can be 6 inches apart in an elevator, but it makes no difference to those 2 people if they are miles apart in reality (no connection to each other - just passing by), being in God's presence doesn't just mean we are "aware" He is there.  It means there is a deep connection with Him, with nothing (no sin) in between us.  Two people in an elevator don't have connection - no bond of love, or unity.  But a husband and wife sharing an elevator can, as long as there is 'nothing between them' (sin between them left undealt with).   In God's presence means being connected in intimate fellowship with the Lord - desiring Him, loving Him, enjoying Him constantly.  And the way in is - keeping God’s Word, always. And repenting when we see otherwise. In other words - it's being a disciple who denies themself consistently, for the purpose of following the Lord.
 
The two strangers in the elevator have no intention of ever having anything to do with each other. They're sharing one physical space for 30 seconds but they are in no way in each other's presence, really.  And neither would two spouses or friends be if they were having deep issues of selfishness and hatred for each other.  They could be 6 inches apart but in reality so distant and cold, like a wall is between them.  To really be in someone's REAL presence (connected), you have to make sure there's nothing (no sins) between you.
 
Isaiah 59:2 "But your iniquities have made a separation between you and your God, And your sins have hidden His face from you so that He does not hear."
 
I've tried many times in my own effort to keep a conscious effort to have an 'awareness of God's presence' in my conscious mind, and failed at it.  "God is here with me, God is here with me..." - like that.  I found that it was just a method I was trying, and it didn't last.  I discovered that God isn't found with methods, or shortcuts.  I'm sure God was happy and sympathized that I was trying, but my efforts did not last, because it wasn't the real way into God's presence.  I learned that in the same way as two married people need to have 'nothing between' them (no outstanding issues) to really be with each other, fellowship with God does not depend on "remembering God" and discipline of reciting prayers or verses at conscious times throughout the day.  It's instead a constant attitude of the heart which says, He is first in everything - I always want to be in God's will and living in a state where He is pleased with me, and I am 'connected to Him', desiring Him.  And when anything at all comes up in the day that may be out of God's will, I quickly veer back to the path which is in God's will.  Because in God's will is in God's presence.
 
That has helped me and I've seen that the more I practice that, the more I actually do have an awareness of His presence, and His joy - without trying to force it.  For me I believe it's a progress, as I press on - not a one-time thing.  So don't get discouraged if it does not come all at once for you. We grow in it.
 
We hear the term 'pray without ceasing.'  And we’ve learned that prayer is like breathing.  Breathing is not about the discipline of remembering to breathe… we just do it because we have life.  God has to be first in our life - our first desire, our first love to be able to do this.  If we have life (God being first in our life), we’ll do these things without ceasing.  If He is our desire without ceasing, we will pray without ceasing.  If He is first in our life without ceasing, will be in His presence without ceasing.
 
It starts when we've made a conscious commitment that the Lord and His will alone is #1 for us.
 
We do not have to be monks or living in monestaries to be living in God's presence all the time.  What a joy!  We can have 'days of heaven on earth' right now, if we commit to make God and His will #1 in everything in our life, and work out our salvation with fear and trembling.  Taking His Word seriously, to obey it.
 
WHAT IS OBEDIENCE, WHAT ARE THE COMMANDS?
Usually 'obedience to the commands' and 'keeping His Word', for most people stops at the 10 commandments - “Don’t do these outward wrong things.”  But it helps me to remember all that Jesus preached on the sermon on the mount - Matthew chapters 5 through 7.   This type of life is what it means to “keep His commandments” in the new covenant.  It's not just outward obedience but inward. See the type of life Jesus talked about there.  Not just outward commands but inward attitudes - don't love money, but love God.  Don't judge unrighteously or hate or hold bitterness, but love your enemies.  Don't live in pride before men, but humility before God alone. Don't be anxious or doubt but be full of faith in God's love and goodness as a Father. To take His Word seriously and obey His commands (both inward in our heart/thoughts, and outward) as disciples, taking up our cross everyday - is the way that God will come and make His home (abode) with us.  Heaven is where the presence of God is, and we can live that type of life now.  That makes me excited that it's possible to live these "days of heaven on earth" with Him right now.  It’s better than any mission trip or monastic life.   “Christ in you, the hope of glory” (Col 1:27).  And when He is there with us and in us, He can drive out sin and self, and Satan, the enemies of God in our life.  But we have to make the commitment to live in a fear of God and diligent reverence to His Word, deciding that He will be #1 in our life.
 
Deuteronomy 11:21 "That your days may be multiplied, and the days of your children, in the land which the LORD swore unto your fathers to give them, as the days of heaven upon the earth." (KJV)
 
See the full passage in context, KJV version:
 
DEUTERONOMY 11:18   Therefore shall ye lay up these my words in your heart and in your soul, and bind them for a sign upon your hand, that they may be as frontlets between your eyes. 
11:19   And ye shall teach them your children, speaking of them when thou sittest in thine house, and when thou walkest by the way, when thou liest down, and when thou risest up. 
11:20   And thou shalt write them upon the door posts of thine house, and upon thy gates: 
11:21   That your days may be multiplied, and the days of your children, in the land which the LORD swore unto your fathers to give them, as the days of heaven upon the earth. 
11:22   For if ye shall diligently keep all these commandments which I command you, to do them, to love the LORD your God, to walk in all his ways, and to cleave unto him; 
11:23   Then will the LORD drive out all these nations from before you, and ye shall possess greater nations and mightier than yourselves.