Crochet winter decorations for the home.
For a bigger acorn, use a bigger crochet hook. The acorn in the image has been made using crochet hooks in sizes 2.5 mm and 3.5 mm.
Ch chain stitch
Ss slip stitch
Dc double crochet stitch
The basic shape:
The bottom of the acorn will be colour 1, and the top of the acorn (cap with stem) will be colour 2.
Start with colour 1:
Start by making a magic circle with 6 dc.
Row 1: (2 dc in next s) x 6 .
Row 2: (1 dc, 2 dc in next s) x 6 .
Row 3-8: dc (x 6) .
Change to colour 2.
Row 9-11: dc (x 3) 
Row 12: (1 dc, invisible decrease) x 6 .
Row 13: (2 dc, invisible decrease) x 6 .
Row 14-15: dc (x 2) .
Finish with an ss, fasten and hide the yarn tails.
Cut a piece of yarn in colour 2 (about 100-200 cm). Using your embroidery needle, make long stitches from the base of stem to the edge of the cap of the acorn. Keep adding stitches until you are happy with the size and shape of the cap.
Attach a piece of string for hanging.
How to do invisible decrease:
The invisible decrease is a way to crochet two stitches together using only the front loops of each of the two stitches and not both the back and front loops like you would do for a normal decrease.
1: First insert your crochet hook underneath the front loop only of the next stitch, then insert the hook underneath the front loop only of the following stitch.
2: Yarn over hook.
3: Draw through the two loops, leaving two loops on your hook.
4: Yarn over hook again, and draw through the two loops remaining to complete the stitch.