One size fits all crocheted slouch ribbed beanie pattern

One size from 2 years old onwards (stretchy model)
Hook 4.5mm
2.5 balls of 100% dk wool for body, 1.5 ball for pompom
Rib stitch
Tension swatch in dc (double crochet) rib stitch: 19sts, 27 rows = 10x10cm square

Make a rectangle of 34 cm height by 37 cm width

Pattern:
Start with 66ch (one of which is a turning chain) (height of hat)
For the rib stitch always remember to only work into the back loop of each stitch!
Foundation row: 1dc (double crochet) into 2nd ch from hook, 1dc into each of the next 64ch (makes 65dc), turn.
Row1: 1ch (turning chain), 1dc into each of the next 65sts  working only into the back loop of each st, turn.
Repeat row1, 99 times in all.
Slip stitch in last stitch leaving a 2 metres long thread to assemble.
Slip stitch side on the inside to make up hat.
Gather and sew the top making sure you don't overlap ribs.
Don't worry about the remaining hole as the pompom will sit nicely on top of it.
To make a big bobble draw around a CD to make cardboard templates.
Before cutting the pompom make sure you stick a small cylinder (glue stick, pen...) in the middle to avoid the threads from going wild.
Find here a 'how to make a pompom' tutorial.
Firmly fix the bobble on top. Weave in ends.
To wear with or without a fold.