Short answer is daily walking in humility to God listening and being guided by the Holy Spirit that is actually inside of you.
Here's a longer answer ,(Edit Add, from Albert Barnes)
Galatians 5:16 Ga 5:16 [This] I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh.
Verse 16. This I say then. This is the true rule about overcoming the propensities of your carnal natures, and of avoiding the evils of strife and contention.
Walk. The Christian life is often represented as a journey; and the word walk, in the Scripture, is often equivalent to live,
Mr 7:5 Then the Pharisees and scribes asked him, Why walk not thy disciples according to the tradition of the elders, but eat bread with unwashen hands?
. See Barnes for Ro 4:12; See Barnes for Ro 6:4; See Barnes for Ro 8:1.
In the Spirit. Live under the influences of the Holy Spirit; admit those influences fully into your hearts. Do not resist him, but yield to all his suggestions. See Barnes for Ro 8:1. What the Holy Spirit would produce, Paul states in
Ga 5:22 But the fruit of the Spirit is love, joy, peace, longsuffering, gentleness, goodness, faith,
Ga 5:23 Meekness, temperance: against such there is no law.
"|. If a man would yield his heart to those influences, he would be able to overcome all his evil propensities; and it is because he resists that Spirit that he is ever overcome by the corrupt passions of his nature. Never was a better, safer, or a more easy rule given to overcome our corrupt and sensual desires than that here furnished. Comp. See Barnes for Ro 8:1, and
Ro 8:2-13 For the law of the Spirit of life in Christ Jesus hath made me free from the law of sin and death. For what the law could not do, in that it was weak through the flesh, God sending his own Son in the likeness of sinful flesh, and for sin, condemned sin in the flesh: That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit. For they that are after the flesh do mind the things of the flesh; but they that are after the Spirit the things of the Spirit. For to be carnally minded is death; but to be spiritually minded is life and peace. Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be. So then they that are in the flesh cannot please God. But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his. And if Christ be in you, the body is dead because of sin; but the Spirit is life because of righteousness. But if the Spirit of him that raised up Jesus from the dead dwell in you, he that raised up Christ from the dead shall also quicken your mortal bodies by his Spirit that dwelleth in you. Therefore, brethren, we are debtors, not to the flesh, to live after the flesh. For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live.
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And ye shall not fulfil, etc. Marg., Fulfil not--as if it were a command. So Tindal renders it. But the more common interpretation, as it is the more significant, is that adopted by our translators. Thus it is not merely a command; it is the statement of an important and deeply interesting truth--that the only way to overcome the corrupt desires and propensities of our nature, is by submitting to the influences of the Holy Spirit. It is not by philosophy; it is not by mere resolutions to resist them; it is not by the force of education and laws; it is only by admitting into our souls the influence of religion, and yielding ourselves to the guidance of the Holy Spirit of God. If we live under the influences of that Spirit, we need not fear the power of the sensual and corrupt propensities of our nature.
{b} "Walk"
Ro 8:1 There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
Ro 8:4 That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.
Ro 8:13 For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live.
{1} "ye shall not fulfill the lust" "fulfil not"
{*} "lust" "desire"
By Albert Barnes