The inked impressions of hand carved stamps are generally 2-dementional. Giving 3-dementional appearance to the stamped images is a challenge for stamp carvers, but developing inking technique to add gradations to the ink is one of the solutions.
This is how I do it.
Preparing wet paper towel, crumpled small Kleenex ball and a peace of Kleenex.
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Making a pad with the Kleenex ball and a peace of Kleenex.
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Appling ink to the stamp.
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Wetting the pad and taking some ink off the stamp by tapping motions.
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This is how the image looks like.
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Cleaning the stamp with wet paper towel.
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I tried with lighter ink to show more transparency of the glass bowl,
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but the impression was too weak.
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So, I added darker ink to the top and bottom of the stamp.
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Added a goldfish in the bowl.