Materials:
DK weight yarn in Colour A (main body) and Colour B (hands/feet/mouth/inner ear. I didn't estimate amount, but you won't need more than 100g for A and more than 50g for B.
1x pair of 4mm needles
Yarn sewing needle
Stuffing
Buttons for eyes
Abbreviations
2tog = knit 2 stitches together
inc = increase (using knit into back of stitch)
Body
CO 60 sts in Colour A
Row 1: k all, then continue knitting until work measures approx 6" (but feel free to adjust for a shorter/longer monkey).
Begin decreases for doming the head:
Row 1: k1, *k2tog, k13, repeat from * 3 times, k2tog, k12 (52)
Row 2: k all sts
Row 3: k1, *k2tog, k12, repeat from * 3 times, k2tog, k11 (44)
Row 4: k all sts
Row 5: k1, *k2tog, k11, repeat from * 3 times, k2tog, k10 (36)
Row 6: k all sts
Row 7: k1, *k2tog, k10, repeat from * 3 times, k2tog, k9 (28)
Row 8: k all sts
Row 9: k1, *k2tog, k9, repeat from * 3 times, k2tog, k8 (20)
Row 10: k all sts
Row 11: k1, *k2tog, k8, repeat from * 3 times, k2tog, k7 (12)
Row 12: k all sts
Cast off, leaving sufficient yarn to stitch back edges together. Once this is done, turn inside-out an and stuff well to (hopefully) achieve a sort of sausage shape. You may need to pummel the monkey into his desired shape a bit! Once stuffed to satisfaction, thread yarn along the cast on edge to create a 'drawstring' and pull then stitch closed. You may well end up with a bit of a 'wrinkly' bottom, as obviously this end isn't shaped, but wrinkles either side of the back seam function quite well as some cute monkey bumcheeks!
Arm/leg (make 4 the same)
CO 10 stitches in Colour B to make foot/hand.k for approximately 1.5" - 2 " inches, then switch to Colour A.
Continue garter stitch for another 5" - 6" or until limb is the same length as your monkey body.
Cast off, and then leaving cast off edge open, stitch the long edges and end of cast on 'foot' part together to form a tube closed at one end. Turn whole piece inside out. (This can be fiddly. I found pushing the 'foot' part inside the tube a little way with my thumb, and then using a large stoppered end of the knitting needle to push in the rest of the way, was easiest.)
Mouth
CO 40 stitches in Colour B.
Knit until work measures 4". Cast off and then stitch together short edges to form a band. Fold in half so long edges meet (i.e. you have a doubled up band). You can stitch long edges together if preferred or stitch together when attaching to body (see below).
Ears (make 2)
To be honest,my ears were a bit of a botch job, so feel free to cut four semi circles of felt, two for each of your two colours (as close as you can match) to form the fronts and backs of your ears. I'll (hopefully) add my attempt at the pattern for the knitted version here soon.
Attaching arms/legs
With Colour A, stitch arms to the each side of the monkey, about half way down, Stitch underneath the arm (i.e. the armpit!) so that that the arms don't lie flat and form little shoulders. Stitch the legs in the same way, directly underneath the arms, about two inches from the bottom of the body.
Attaching mouth
Arrange the mouth band in an oval, with the folded end outward the other edge to the body. Flatten the outer edge of the band and pin in place if desired. With Colour B, stitch around the inside edges of the band, following the shape of the oval.
Sew on two buttons for eyes, and stitch a cross on front of body in Colour B for a belly button if desired. You can also add a tuft of hair by looping a double strand of Colour A at the top of the head, and trimming to length.