Here is a lightly shaped beanie with a lace Shamrock design. This pattern comes with instruction for seven sizes from Toddler through Adult (XL). Knitted In-the-Round, it uses Size 5 US needles and sport weight yarn. There is a chart for the shamrock design, as well as written out instructions.

Sizes
Toddler: Head circumference of about 18 inches
Child (M): Head circumference of about 19 inches
Child (L): Head circumference of about 20 inches
Teen: Head circumference of about 21 inches
Adult (M): Head circumference of about 22 inches
Adult (L): Head circumference of about 23 inches
Adult (XL): Head circumference of about 24 inches

From 100-230 yards of Sport Weight yarn.

Less than 2.5 oz Sport Weight yarn. (Model used Hobby Lobby I Love This Yarn)
Size 5 US (3.75 mm) needles in whatever combination of circular and/or double point needles you use to knit by your In-The-Round method; or size to obtain gauge.
3 markers
Measuring tape, Scissors, Tapestry Needle