We have to create its shadow now. For the beginning we have to copy the balloon's layer and make the lowest copy entirely black, choosing Image ? Adjustments ? Channel Mixer.

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Distort the shadow, applying Edit ? Transform ? Distort.

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We have to use now the layer's mask and the Gradient Tool with a long extension to make the shadow more transparent on the bottom part.

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Blur out a little the layer: Filter ? Blur ? Gaussian Blur.

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