Small Eyelet Buttonhole
These are the simplest buttonholes. They are also the ones most commonly used by hand knitters.
At the point of the desired buttonhole, transfer 1 stitch to the needle on the right or left. Transfer direction does not matter, but be consistent; that is, for every hole in the band, transfer either to the adjacent needle on the right, or the adjacent needle on the left, but do not mix the transfer directions.
Bring each emptied needle back to position B. When you knit the next row, it will lay a strand of yarn in the needle hook.
On the next row, it will begin to knit normally. Check each buttonhole at this point. The stitches should have knitted off cleanly. If they did not, manually take each stitch through.
Large 2-stitch Eyelet Buttonholes
These 2-stitch eyelets will accommodate a large button. The holes are not as even and professional-looking as other styles, and wear longer if finished by hand sewing around them with matching yarn.
At the point of the desired buttonhole, transfer 1 stitch to the needle on the right and one stitch to the needle on the left. Bring the emptied needles back to position B.
Knit 1 row. The yarn will strand across both emptied needles. Remove the yarn from the right needle, and be sure it remains in position B.
Knit 1 row. The left needle has knitted a stitch, and a strand of yarn is now in the right needle hook. Using a transfer tool, pick up the strand of yarn you dropped in Step 2 above; hang it in the hook of the needle just to the right of the buttonhole.