You bought the frame, you know which wall it belongs on, and the drill is charged. Then the picture ends up eight centimetres too high, the nail vanishes into crumbly plaster, and the mirror above the fireplace has developed a lean. Hanging art isn't difficult work. Almost all of the difficulty happens before the first hole is drilled.

These are the mistakes that cause the most patched walls and re-drilled holes, and what to do instead.

Hanging everything at your own eye level

Most pictures end up too high. People stand close to the wall, hold the frame up at shoulder height, and drill. Step back and it looks like it's floating near the ceiling.

A useful starting point, borrowed from galleries: put the centre of the artwork roughly 145cm (about 57 inches) from the floor. That's comfortable for a wall you stand in front of, such as a hallway or above a console table. Adjust it for how the room is actually used. Above a sofa, sit down first and have someone hold the frame — a gap of 15–25cm above the sofa back usually looks right, and it stops anyone's head hitting the glass.

Then look for alignment. If you have window heads or door frames on the same wall, lining the top of the picture up with them makes a room feel deliberate rather than accidental.

Not checking what's behind the plaster

Plasterboard hides timber studs, electrical cables and pipes, and none of them announce themselves. Before you mark anything:

• Run a stud finder across the wall on its deep setting and mark the stud edges lightly in pencil. A magnet that finds the screws holding the plasterboard works well too.
• Cables usually run in straight lines from sockets, switches and ceiling fittings. Keep a generous margin — 15cm either side — and never drill directly above a socket or switch.
• Kitchens, bathrooms and the wall behind a radiator are where pipes hide. Use a detector that picks up metal and live cables rather than guessing.
• In older properties with lath and plaster, expect a hollow, crumbly layer behind the surface. Fixings need to reach the timber, not grip the plaster.

If the wall gives you any reason for doubt, stop and get a second opinion. A small hole is easy to fill; a punctured pipe or cable is not.

Using whatever hardware came in the box

The nail taped to the back of a cheap frame is usually the weakest part of the job. It might hold a light print in solid plaster. It will not hold a framed poster in a deep moulding, and it has no chance against a mirror.

A rough guide to fixings

• Light frames: a proper hardened picture hook with a thin pin, angled slightly downward into the wall.
• Medium frames: two hooks, or hollow-wall anchors that expand behind the plasterboard.
• Heavy frames and mirrors: screws into studs, toggle bolts, or a French cleat fixed across two studs.

Every fixing comes with a weight rating on the packet, and that rating assumes a perfect wall and perfect installation. Stay well under it. If a product claims a limit, treat half that figure as your realistic ceiling.

Relying on one hook and a length of wire

Picture wire is convenient. It's also the reason so many frames sit away from the wall, tilt slightly, and drift out of level within a week. A single hook gives the frame a pivot point, so any vibration sets it swinging.

Two D-rings and two hooks solve most of this. The frame hangs flatter, the weight is spread across two points, and it holds its level. For anything wider than about 30cm, or anything with glass in it, use two fixing points — no exceptions. If a frame has no D-rings, they're inexpensive and easy to screw into the back of the moulding.

Marking the frame, not the fixing

This is the classic error. You decide the top of the frame should sit at a certain height, mark the wall there, and drive the nail in at that point. The frame then hangs above the mark, because the hook sits below the wire or D-ring. Half a centimetre of hardware becomes five centimetres of wrong.

Cut a paper template to the size of the frame, mark the hanging points on it, and tape it to the wall. Look at it from the sofa, from the doorway, from the kitchen. When you're happy, push a nail through the template marks into the wall to leave a starting point, then tear the paper away.

If you'd rather measure: mark where the top of the frame will sit, measure down the back of the frame to the hanging point, then measure that distance up from your line. That's where the hook goes.

Treating a heavy mirror like a lightweight print

A large mirror can weigh more than you'd guess, and glass doesn't survive a fall. Fix into studs wherever you can, use two or more substantial fixings, and consider a French cleat — a metal or timber bracket that spreads the load along its full length rather than at one point.

Two practical points. Add small rubber bumpers to the bottom corners of frames and mirrors. They stop the piece drifting out of level when doors close or someone brushes past, and they keep the frame off the plaster so air can move behind it. And if the piece is heavy, valuable, or destined for a wall you're not sure about, it's worth having someone experienced take it on. A handyman can usually hang and level several pieces in one visit, which is cheaper than replacing a mirror or repairing a water-damaged wall.

A five-minute routine before you drill

1. Decide the centre height with a tape measure, not by eye, and check it from where you'll actually sit.
2. Run the detector across the wall. Mark studs and note anything to avoid.
3. Weigh the piece roughly, then choose fixings with a comfortable margin.
4. Make a paper template, tape it up, and leave it there for a few minutes before committing.
5. Drill, fit the fixings, hang, and check level while pressing the frame gently against the wall.
6. Step back, look again, and only then fill the pencil marks.

One extra minute with a tape measure and a piece of paper is the difference between a wall that looks finished and a row of small grey holes you'll be filling in next spring.

Photo: Sheep . / Pexels