In my opinion everyone should have a corner punch. It is so useful and makes such a difference with small means. Now you cannot only use it for rounding the corners, you can also use it to make a scallop edge. You need to carefully remove the guide and then you just pusch it up-side-down against the paper and create the scallopes, one after another. Super easy.
As I said, I used it on my Tinker Bell August Class kit to make those 2 green vertical scalloped stripes behind the center pattern paper. Go ahead and try it if you haven't already!
Of course you can always free-hand cut as well.
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