Make a chain with an uneven number of stitches. I chained 25 for this example.

Row 1: Dc in 4th ch from hook and across. Ch 3, turn.

Row 2: FPdc around second dc, dc in next dc, [FPdc, dc] 9 times, FPdc, dc in turning ch, ch 3, turn.

Row 3: BPdc around second dc, dc in next dc, [BPdc, dc] 9 times, BPdc, dc in turning ch, ch 3, turn.

Repeat Rows 2 & 3 until you have desired length of ribbing.

This style of ribbing is great because it has excellent stretchability and you can begin working your sweater pattern without having to change your stitch count. You don't even have to flip it when your done, because the stitches are already going in the right direction.

I used a fairly large hook in the example above. By using a smaller hook, such as 5mm or less, you can tighten up the ribbing. Don't worry, it stretches and springs back to size and shape.