Used two threads. One unknown off-white wool and some left over sockwool.
Cast on 40 st. on 2 circular needles. Pattern: K3, P2. for 13 cm. Put last 4 st. from the needle you are working on and first 4 st. of next needle on piece waste yarn. Knit on until 21 cm. Bind off loosely. Pick up 8 st. on first circular needle and 8 st. on another one. Knit in the round for about 2 cm. Bind off loosely.