You can make these creepy Halloween Tarantula Spider decorations in three different sizes
They are knitted around ball pool balls and ping pong balls.

Small – 12.5 mm (ping pong/table tennis ball)
Medium – 17 mm (small ball pool ball, mine were from a pound shop in net bags of 15.
Large – 20 mm (regular size ball pool ball which I have found in supermarkets and charity shops.)

They are a great way to recycle plastic balls.

The spiders legs have chenille pipe cleaners to make them poseable.

I use beads for their eyes

The yardage includes all the yarn. The smallest spider takes approximately 14 grams ( 52 yards) Medium 21 grams (77 yards) and the large 30 grams (110 yards)

The skills required are cast on, cast off, knit, purl, increase (by knitting in the front and back of stitch), decrease by knitting/purling two stitches together) and stripes (tying on a second colour and cutting the last colour).