Once the steel strings are securely attaching to the bridge pin, you can focus your attention on the headstock. The steps for attaching steel strings to the tuning post of an acoustic guitar are slightly different for the treble strings (G, B, E) and the bass strings (E, A, D).
To attach a treble string to the tuning post, follow these steps:
Pass the string through the hole in the post.
Be sure that the strings go into the correct slot in the nut. Leave enough slack between the bridge pin and the tuning post to enable you to wind the string around the post several times.
Kink (or crease) the metal wire toward the inside of the guitar.
Leave enough slack for winding.
While keeping the string tight against the post with one hand, wind the tuning peg clockwise with the other hand.
This step is a bit tricky and requires some manual dexterity (but so does playing the guitar). Keep your eye on the post to ensure that as the string wraps around the post, it winds down, toward the headstock surface.
Winding the string downward on the post increases what’s called the breaking angle. A sharper angle brings more tension down onto the nut and creates better sustain. To get the maximum angle, wind the string so that it sits as low as possible on the post. (This fact is true for all guitars, not just acoustics.)
To attach a bass string, follow the same steps except that you wind the strings counterclockwise in Step 3 so that the string goes up the middle and goes over the post to the left (as you face the headstock).