A gallery wall is one of the fastest ways to make a room feel properly finished, whether you are covering a bare chimney breast or bringing colour to a hallway that never quite came together. The trouble, of course, is the holes. Nobody wants to hand back a deposit with a constellation of filler patches, and nobody wants to spend an afternoon drilling when a gentler approach will do. The good news is that a well-planned gallery wall can be almost entirely reversible, and it will look better for the planning.

Plan the Layout on Paper First

Before anything touches the wall, sketch it. Cut paper or card templates to the exact size of each frame, then arrange them on the floor until the composition feels right. Photograph the arrangement, or better still, tape the templates to the wall with low-tack masking tape and live with them for a day or two. It sounds fussy; it saves an awful lot of refilling.

A few arrangements that reliably work:

• A grid of same-sized frames, usually three by three or two by four, which looks calm and deliberate.
• A salon-style cluster, built around one larger anchor piece with smaller frames filling the gaps.
• A single horizontal row above a sideboard or console, which suits narrow walls and low ceilings.
• A picture shelf or picture rail, which needs no fixings in the wall at all and lets you swap prints whenever the mood takes you.

Mark the centre line of each template with a pencil dot. That dot becomes the hanging point, and it is the only mark you should ever need to make on the wall itself.

Choose Fixings That Forgive You

For anything up to about two kilograms — small prints, lightweight frames, unframed canvases — removable adhesive hooks and strips are genuinely brilliant. Buy more than you think you need and check the stated weight limit, then halve it. A frame that weighs just under the limit will still come down the first time a door slams.

Strips and hooks need a clean, dry, flat surface. Wipe the wall with a damp cloth and let it dry completely. Avoid using them on freshly painted walls, where the paint has not fully cured, and steer clear of damp spots such as directly above a kettle or in a steamy bathroom. Follow the maker's instructions on pressing and resting time rather than guessing; the difference between a strip that holds for years and one that gives up overnight is usually patience.

For heavier frames, do it properly. A single screw into a stud or a plasterboard fixing is safer and far less stressful than a hopeful strip. One well-placed hole is not a disaster, and a dap of filler will close it in seconds when you move on.

Get the Spacing and Height Right

Two numbers do most of the work here. First, hang the group so its overall centre sits roughly 145 to 152 centimetres from the floor. That is comfortable eye level for most people and stops the arrangement from drifting upwards over time.

Second, keep the gaps between frames consistent, usually 5 to 8 centimetres. Tighter gaps look collected and intentional; wider gaps look accidental. If the wall sits above furniture, leave 15 to 25 centimetres between the sofa back or sideboard top and the bottom edge of the lowest frame, and aim for the whole arrangement to span roughly two-thirds of the furniture's width.

Hanging Day: Templates, Levels and Two Hooks

Work from the centre outwards. Tape your paper templates back onto the wall in the final arrangement, then use a spirit level to check every row. Pencil a faint dot at the hanging point of each frame before you remove anything.

Where you can, use two hooks per frame rather than one. It costs a little more time and stops pictures tilting the moment someone brushes past them. Small self-adhesive rubber bumpers on the bottom corners will also keep a frame sitting flat against the wall, which is especially useful on older, wobbly plaster.

Adhesive strips are removed by stretching them slowly downwards, never by pulling outwards. Take your time and warm the wall slightly with a hairdryer on a cool-to-warm setting if the strip feels stubborn.

Living With Your Wall

A gallery wall should not be finished the day you hang it. Leave it a fortnight, then swap one print for something new, add a small frame into a gap, or move a piece that never quite sat right. Because you planned the layout on paper and used fixings that come away cleanly, changes cost you nothing but a few minutes.

Keep a note of where the original hanging points are, and keep a small pot of touch-up paint in the cupboard. When the day comes to move out or redecorate, a fingertip of paint over each tiny mark will have the wall looking as though nothing ever hung there at all — which is exactly the point of doing it gently in the first place.