Four-Fingered Glove

If you're knitting a glove without a thumb, index finger, or pinky you'll need to be able to decrease stitches both so that they lean left and lean right.

If you're knitting a glove without a middle finger or ring finger, then you'll only need to know how to sew a Kitchener stitch.

Assuming that the finger is missing down to the knuckle, you can use decreases along that length to make a neat triangle with the base at the knuckle's start and the top where the rest of the fingers begin.

To math out the distribution of decreases you'll need to divide your number of stitches into quarters, so you'll know how many stitches per finger you have. (eg- if you have forty stitches, you'll want to remove ten stitches for a missing index finger) and how many rows you'll be knitting between the base of the thumb and the base of the fingers. Every row will have two decreases on either side of the missing digit (left- and right-leaning). So to follow our example, you're knitting 40 stitches around the palm, you want to decrease ten stitches to make up for the missing index finger, and you know that you have five rows to knit before you reach the base of the fingers. So you want to decrease two stitches every two rows. I would then suggest decreasing two stitches every other row.

You could also decrease one every row because the math is the same, but you might want to take into account the appearance of the stitch work:

This is specifically for when the ring or middle finger stops at the base of the fingers.

When you reach the base of the fingers, divide the number of stitches you have by four so you'll know how many stitches you have per finger. (eg- if you have 40 stitches, then that will mean about ten for each finger)

Place each set of stitches on a knitting needle, with half on each, and then graft the section shut using Kitchener stitch.

This is absolutely the easiest: just don't knit the gusset, or otherwise increase the number of stitches while knitting the hand.

This is probably the second easiest to do: you'll want to know how many stitches you need to decrease until you have just three of four left, and decrease the same number of stitches for each round. Then just sew it shut! Just the same way as you would finish fingers regularly