How to stick letters on a wall

No drill and no crooked lines. All you need is a paper template, a spirit level and ten minutes.

Step by step

Clean the wall with a cloth and isopropyl alcohol and let it dry. Freshly painted walls need a few weeks to cure.
Lay the letters on the floor in the order and spacing you want, and take a photo.
Draw the baseline with a pencil and a level, and mark the centre of each letter on tracing paper or masking tape.
Stick a piece of double-sided foam tape on the back of each letter, leaving no loose edges.
Peel off the liner, set the letter on its mark and press for about 30 seconds.
Wait 24 hours before touching them or cleaning the wall around them.

On smooth painted walls, double-sided foam tape is usually enough. On rough, textured or unpainted plaster surfaces, use mounting adhesive.

For outdoor use, choose an outdoor-rated mounting adhesive and avoid sticking in the rain or below 5 °C.

All that is left is deciding what to write.