You use a free app called iC Brushes. Here I've chosen an existing group. To add to the group, I tap the landscape button with the + above the thumbnails.
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I choose the artichoke image I've saved.
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It is added to the group, and I choose the arrow at the upper right to save. I want to save the group within iC Brushes as well as to iColorama.
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There's another step to get it into iColorama.
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iColorama is opened and the group appears within Imported Brushes. Since the group was already there, it is appended, resulting in duplicates.
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The brush is ready to use.
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I had to pay $1.99 for it just now... [emoji53]
I see the brush inside iColorama but I can't figure out how to use it.