I do know that years ago I found a template on Laren Meader's blog where she showed how she made a onesie card. It is an A2 size card and I've done so many over the past few yeras that I know the directions by heart. They are super simple and I generally make them for my DD's friends who have had or are having babies. I give them away as an extra little gift from me so they can send out either thank you's or announcements ~ whichever they would like.
I guess it depends on how many you'd like to make and how much time you have. I can generally make 10 complete cards with matching envies just after dinner.
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