Knit top down with raglan style increases and a v-neck, then stitches are picked up for the button band.

Materials:
any DK yarn, you can get at least 2 cardigans from a single ball of Premier Basix DK

4 or 5 buttons (depends on where the buttonholes are placed)

US 4 and US 6 circular needles, you will need a cord long enough to knit the button band

Let me know if you have any questions!