In December the light is gone by five o’clock, and a room lit only by its ceiling light feels bleak. String lights fix that faster than anything. And they don’t need a tree: some of the best uses of Christmas lights are nowhere near one.

A few rules first, then the ideas.

Three rules

Warm white only. Cool white LEDs look blue and harsh indoors. Look for “warm white,” around 2700K. Colored lights are lovely on a tree, but around the rest of the room they quickly become a lot.

Hide the wire. Clear or green wire disappears against glass and greenery; copper wire disappears against wood. Clear adhesive clips (on Amazon) keep strands neat along walls and window frames, and they come off without marks.

Put them on a timer. A smart plug (on Amazon) or simple timer turns everything on at dusk and off at bedtime. You’ll actually see them every evening instead of forgetting to switch them on, and you won’t leave them on overnight.

Around a window

The one from the photo, and the best place to start. Run a strand of fairy lights (on Amazon) around the inside of the window frame with clips, or let it drape loosely across the top. Lit windows look lovely from the street too.

For a fuller look, hang curtain lights (on Amazon) (vertical strands on a single wire) behind a sheer curtain. The fabric softens the light into a glow.

Along a shelf or bookcase

Weave a strand along the front edge of a bookshelf, or tuck it behind the books so only the glow shows. Same on open kitchen shelves, a sideboard or a TV unit. Battery strands are handy here, since bookshelves rarely sit next to an outlet.

In a vase or jar

Coil a battery strand of fairy lights inside a big glass vase, a lantern or a jar. Instant table centerpiece, and no heat, so it’s safe. A tall vase of lit branches (on Amazon) does the same at a bigger scale and fills the corner where a tree would go.

Across the ceiling

For a bigger room or a dining area, globe string lights (on Amazon) draped across the ceiling in a couple of loose swoops look festive and stay up happily into January. Hang them from small adhesive hooks at the corners.

Behind the headboard

A strand along the top of a headboard or tucked behind it gives a soft light for reading in December, and replaces the bedside lamp for the season. Lovely in a kids’ room too, on a timer so they turn off once everyone’s asleep.

On a mirror

Run fairy lights around a large mirror, in the hallway or entry. The mirror doubles the light.

Over a doorway

A garland over a door frame with lights woven through, or just a strand of lights along the top, marks the entrance to a room. Easy in a rental with clips.

Inside a cabinet

Glass-front cabinets with a strand of battery lights inside, behind the glasses or plates, look beautiful and take thirty seconds.

When to take them down

You don’t have to. Warm white lights around a window or a shelf aren’t really Christmas decorations; they’re winter ones. Many people leave them up until February. More on that in what to keep up after Christmas.