The baby suit, or onesie, for me is one of the best symbols in baby theme.
Many days ago I have drawn up and used my own onesie chart for cross-stitch embroidery.
This is the time to turn it into the knitting chart.
Enjoy!

As an option you would need a 2.5-3mm crochet hook to make a loop, but you can also knit an i-cord for these purposes or just skip it.