Help! I'm 'Knew'!

I know how to knit, but reading those patterns are the difficult part. How do I know how many stitches to cast on? I am doing a 12 mth baby sweater that says finished size 22" and then goes right into Garter St Ridge pattern (16 stitches). I am lost and frustrated not understanding the ‘language’ of knitting!!

Keep reading the pattern and you’ll find where it says “CO X sts.” Often patterns will have the stitch pattern at the beginning, then you refer to it later when it says to work in pattern after casting on.

Also, if the pattern will make, say, a 6-month, 12-month and 18-month size, and it says something like “CO 42-45-47 sts”, understand it means “for 6-month, cast on 42, for 12-month, cast on 45 for 18-month, cast on 47”. It also helps if you highlight or circle the stitches needed for the size you’re working on, because when you shape shoulders or whatever there’s often a “knit 5-6-7 purl 4-6-8” or somesuch. It’s good to rad through the pattern and circle what you’re going to need so you don’t get confused later on.