For an average 3-6 month size. Use a heavier gauge for a bigger cap, or lighter for a smaller.
Size E/4 Crochet Hook
Two colors of handspun, around 13 wpi
Gauge- 5 dc per inch
                4 dc rows per inch
This baby cap offers almost-instant crochet gratification.  It reminds me of the caps the babies wear in old Dutch paintings.  Because of the shaping, it stays on the head phenomonally well, but if Baby is a hat plucker, you can easily add I-cord ties or ribbons or a strap with a button.  In girlish colors it has a delicate look, but in boyish colors the zigzag effect of the V stitches will be quite effective.  I used oatmeal colored BFL, dyed with koolaid, and naturally colored camel silk for my yarns.
Abbreviations and Terms
MC: main color
CC: contrasting color
st: stitch
sk: skip
sl st:  slip stitch
sc: single crochet
dc: double crochet
trtr: triple treble crochet
V stitch: dc, ch1, dc in the same space
cluster:   a pair or group of stitches share the top loops.  Used in this pattern for decreasing. Directions for making a cluster can be found here:
ch 72
Row 1   Dc, ch1, sc in third ch from hook, sk 1, * dc, ch1, sc, in next ch, sk 1.  Repeat from *, ending with sc, ch3, turn.
Row 2    *Dc, ch1, sc in ch1 space, repeat from * across, ending with sc in turning ch from row 1.  ch3, turn.
Repeat Row 2 for three more rows.
Row  6    Using CC, sl st across in back loops only. 
Row 7     Using MC, slst in back loop of 1st sl, c 3, dc across in back loops only
Row 8     Sl st in 1st  st, ch 3; dc in each st across. 
Row 9     Using CC, sl st in first st, ch 3, sk next st, * V st between next 2 st, sk 1, repeat from * across, turn
Row 10  Using MC, ch 3, 2 dc in each ch1 space of V stitches across.  DC in top of ch 3 from last row, ch 6, join with sl st to top of ch 3 at beginning of the row.
From this point, the cap will be worked in the round, right side facing.
Round 1  ch3, dc in each stitch in round ending with dc in each of 6 ch from last row, sl st in top of ch3
Round 2   Using CC, ch4, dc in same space, sk 1 * V st between next 2 st, sk1, repeat from* around, sl st in 3rd ch of ch 4 at beginning of round.
Round 3   Using MC, sl st under next ch, ch 3, dc in same space,  work a 2 dc cluster in each ch1 sp of V st around, sl st in top of ch 3.
Round 4   Ch 3, dc in each st around, sl st in top of ch 3
Round 5   Using CC,  ch 4, dc in same space, sk1 * V st between next 2 st, sk1, repeat from * around, sl st in 3rd ch of ch4 at beginning of round.
Round 6   Using MC, sl st under 4th ch, ch 5, trtr in same space, *  work a 2 trtr cluster in each ch1 sp of V st around, sl st in top of ch 5.
Round 7   Using CC, ch3;  work one dc in space between each trtr cluster around, sl st in top of beginning ch 3.
Round 8   Ch3; *work 2 dc cluster over next two st , repeat from * to the end of the round, sl st in ch 3. 
Cut yarn and weave in ends.
Donna B. is married with six children ages 7 and under.  She has loved the fiber arts since childhood when a family friend taught her to crochet.  She taught herself knitting as a teenager, knitting socks way before it was cool; dabbled in spinning dog hair using a knitting needle for a twisty stick; and tried growing an experimental variety of cotton in central PA.  She crocheted her wedding dress.  When the kids started coming, she put the fiber arts on  hold, but when the twins arrived early this year, she realized it was "now or never!"  So she has been spinning up her daydreams ever since, and blogging about it here