A carved mask is one of the more demanding objects to hang, because it is figurative, it is face shaped, and it carries associations that a landscape print does not. Hung well it is one of the strongest pieces on a wall. Hung badly it reads as either a souvenir or a museum case.
One reads differently from several
The first and most important decision. A single mask on a wall reads as a sculptural object that someone chose. Six masks in a grid read as a collection, and a collection of masks specifically evokes the ethnographic display, which is a register most people do not intend.
If you own several, resist the wall of them. Two well spaced, or one prominent and others in different rooms, keeps each one an object rather than a specimen.
Height, and the face to face convention
Masks want to be at or near face height, which for a standing viewer means the centre at around 150 to 160cm.
The reason is direct. A face hung high looks down on you, which reads as authority or menace. A face hung low is looked down upon, which reads as neglect. A face at your own level meets you, which is how these objects were originally encountered, since a mask was worn by a person standing in front of other people.
That is one of the rare cases where the practical display advice and the original context point the same way.

Space around it
Generous. A mask needs plain wall to read against, because the carving is the whole interest and a busy background competes with it.
As a rule, leave at least the width of the mask again as clear wall on either side. Our 27 by 20cm masks are modest in size, which means they need a modest wall rather than a large one, or they will look lost.
Lighting is the whole thing
More than for almost any other wall object. A mask is a relief with deep recesses, and its entire character lives in shadow.
Light it from one side at a shallow angle so the carved depth throws shadow across the face. The effect is dramatic and it is what makes a mask look like sculpture rather than a plaque. Overhead lighting from directly in front removes every shadow and flattens the piece completely.
Be aware that strong side lighting on a face is theatrical, which suits some rooms and unsettles others. In a bedroom it can be too much. In a hallway it is exactly right.
Which walls suit
Hallways, landings and stairwells work well, since these are transitional spaces where a strong object is passed rather than sat with. A study or a home office wall suits a mask, particularly on a side wall rather than behind a desk on camera.
Living rooms are workable on a side wall. Directly above a sofa, a face looking out across the room where people sit and talk is a strong presence, and some people find it uncomfortable after a few weeks.
Bedrooms are the one to think hardest about. A carved face opposite a bed is a personal decision and worth living with mentally before drilling.
Avoiding the ethnographic look
Four things create it, and all are avoidable. Grid arrangements. Symmetry. Labels or plaques of any kind. And grouping masks with other objects from the same broad region as though building a themed display.
The opposite approach works: one mask, off centre, in a room of otherwise unrelated things. That reads as a person who liked an object, which is the truth.
What sits beside one
Ideally nothing on the same wall. Below, a console or a chest with one or two items. Plants work well, as they do with most carved pieces, because the softness contrasts with the hard geometry of a carved face.
Avoid other faces. Two carved faces on the same wall, whether masks, heads or portraits, compete for attention in a way that neither survives.
Fixings
These are light pieces at this size, so a single picture hook or a plasterboard fixing is sufficient. Check whether there is a keyhole slot or a cord on the back, and use whichever the piece provides rather than improvising.
Hang it, then live with it for a day before deciding on the height. Faces are unusually sensitive to a couple of centimetres either way, and it is worth the second look before you fill the first hole.
Questions people ask
How high should a wall mask hang?
Centre at around 150 to 160cm, roughly face height for a standing viewer. Hung high a face looks down on you, hung low it is looked down on, and at your own level it meets you.
Should I hang several masks together?
Better not. A single mask reads as a sculptural object someone chose, while a grid of masks evokes an ethnographic display. Two well spaced, or one per room, keeps each an object.
How should a carved mask be lit?
From one side at a shallow angle, so the carved recesses throw shadow across the face. Overhead light from directly in front removes all shadow and flattens the piece.
Where should I not hang a mask?
Think carefully about a bedroom, where a carved face opposite the bed is a personal decision, and about directly above a sofa, where a face looking across a conversation can become uncomfortable.
What should I hang next to a mask?
Ideally nothing on the same wall. A console below with a couple of items works, as do plants. Avoid other carved faces, which compete for attention.