There could be months of bible-study devoted to searching out all the 'parts' of the whole armour, knowing that no scripture is it's own interpretation.
Eph 6:10 Finally, my brethren, be strong in the Lord, and in the power of his might.
Eph 6:11 Put on the whole armour of God, that ye may be able to stand against the wiles of the devil.
Eph 6:12 For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.
Eph 6:13 Wherefore take unto you the whole armour of God, that ye may be able to withstand in the evil day, and having done all, to stand.
Eph 6:14 Stand therefore, having your loins girt about with truth, and having on the breastplate of righteousness;
Eph 6:15 And your feet shod with the preparation of the gospel of peace;
Eph 6:16 Above all, taking the shield of faith, wherewith ye shall be able to quench all the fiery darts of the wicked.
Eph 6:17 And take the helmet of salvation, and the sword of the Spirit, which is the word of God:
Eph 6:18 Praying always with all prayer and supplication in the Spirit, and watching thereunto with all perseverance and supplication for all saints;
I can't do months of bible-study in a forum post, but maybe I can point out a few things that spring immediately to mind.
Loins gird about with truth. Joh 14:6,7 Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me. If ye had known me, ye should have known my Father also: and from henceforth ye know him, and have seen him.
Breastplate of righteousness 1Th 5:8 But let us, who are of the day, be sober, putting on the breastplate of faith and love;
Eph_5:9 (For the fruit of the Spirit is in all goodness and righteousness and truth;)
Feet shod with the preparation of the gospel of peace. Isa_52:7 How beautiful upon the mountains are the feet of him that bringeth good tidings, that publisheth peace; that bringeth good tidings of good, that publisheth salvation; that saith unto Zion, Thy God reigneth!
Shield of faith. 2Co_5:7 (For we walk by faith, not by sight:)
Gal_2:20 I am crucified with Christ: nevertheless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.
Helmet of Salvation. 1Th 5:8-10 But let us, who are of the day, be sober, putting on the breastplate of faith and love; and for an helmet, the hope of salvation. For God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ, Who died for us, that, whether we wake or sleep, we should live together with him.
Sword of the Spirit (which is the word of God). Joh_6:63 It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, they are spirit, and they are life.
1Co_2:4 And my speech and my preaching was not with enticing words of man's wisdom, but in demonstration of the Spirit and of power:
The girdle, as I understand it, holds the gear of the soldier, including his sword. The breastplate is a defense for the vital organs, like the heart and lungs. The footwear enables the march and the battle on foot. The shield is a defense against the offensive weapons of the enemy. The helmet protects the head. The Sword is a multi-use weapon, and is, as Paul explained, the Word of God, which is Spirit. All of these terms are "spirit". This is a parable. All of the soldier's accouterments and their functions have a spiritual significance to us, who battle NOT against flesh and blood. Nor is it OUR flesh and blood that we are defending, but the qualities and fruit of the Spirit within us.
Maybe all of that (and more) will help you answer "How" we put it on.