Extremely pale skin is probably the first thing you need to start to look like Caliban.
This make-up is perfect, while you are at it don't forget to temporary dye your eyebrows in platinum blonde.

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Caliban has greyish eyes with notes of green and blue. This contact lens gives a very similar effect.

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Caliban's straw hat. Get rid of the chin cord to perfect the look.

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The goggles are custom made for the show but those are a pretty close match, especially if you add a blue mirror tint to them with an adhesive film.
Also, if you have a motorcycle they are definitely worth it.

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The scarf that Stephen Merchant wears for his Caliban role in the Logan movie is a white and orange foulard/bandana.
This apricot handkerchief is a close match, but if you have drawing skills you can make a movie replica from this pocket square.

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The poncho that Stephen Merchant wears for his Caliban role in the Logan movie is actually a simple piece of fabric wrapped around his shoulders. This cotton fiber rug will give a similar effect.  Check Price