The other day, I experienced a decorating first. My sister-in-law called asking for some quick styling advice. She recently started a new furniture line and was having the pieces photographed in a real-room setting. But like many people who tackle outfitting a room, she had neglected to consider the importance of accessories. There was no time for me to give her a crash course in Styling 101, so instead we FaceTimed. Phone to phone, she guided me from one side of her room to the other, allowing me to select, move and place books, vases, photos and trinkets on various surfaces. In 30 minutes we had a bookshelf, dresser, bed and two tables looking photo-shoot ready.

A week later she called to thank me for my help. With before and after photos of the room in hand, she could see the difference strong styling made. Rooms — even the most modern and streamlined — look like generic furniture showrooms without stuff. Well-placed accessories gave her room visual interest and energy. She asked to schedule our next FaceTime styling session, but instead I insisted that with a few tips she would be able to do it herself. So borrowing from lessons I learned studying art history and from my experience as a magazine editor, stylist and decorator, I sent her the following list of accessories and how to use them.

The stuff

By definition, accessories are nonessentials — throw pillows and blankets, framed pictures, books and objects — but really, they’re what makes a room look lived in. Soft goods, such as pillows and blankets, add warmth while pictures and books add personal notes. And because they’re a room’s most affordable element, you can switch them in and out with the seasons.

•Throw pillows. In a practical sense, these are handy on sofas with a deep pitch; use them to prop up your back so you don’t sink in too deep. They also are an excellent way to add punches of color and pattern to a room. Use a mix of squares, lumbars and bolsters.

•Throw blankets. Fold one on the edge of a modern sofa to soften hard edges or pile two on a bench or stool to add a splash of color.

•Books. Small stacks of varying heights add architecture to coffee tables, side tables or front-hall tables. Pick titles that reflect your interests and hobbies. And don’t be afraid to undress books: removing the glossy covers often reveals bright fabric bindings. Also, when creating tableaux on side tables, bookshelves or a mantle, use books to raise items that are too small or too short.

•Vases and objects. Display items that mean something to you, such as decorative bowls that you picked up while traveling, an heirloom box that was handed down to you, or a popsicle-stick sculpture made by your child. But also pay attention to form. If you choose to display a square box, complement it with a curvy vase.

•Framed photos. Pick your favorites, frame them simply and in a similar style (like all silver), and set out a small grouping instead of scattering them throughout the room.

•Flowers and plants. Every room needs a living natural element. A houseplant or fresh flowers from the grocery store will do.

The rules

1. Act like a curator. Loving stuff is not the same as displaying stuff. Think of home accessories as you would jewelry. You would never wear all of your earrings, necklaces and bracelets at once, nor should you display all of your objects at once.

2. Group like objects together. Whether items are linked by color, shape, or material, groups of objects often have more presence than single objects spread throughout a room.

3. Always display items in odd numbers. Trust me, one item or a grouping of three things looks better than a grouping of two or four.

4. Pay attention to shape. If all of the furniture in your room is boxy, then opt for several objects with shapely curves.

5. Show off your personality. Accessories are what make a house a home. Items don’t have to be expensive, but they should have a connection to you, thereby making your room feel more grounded and real.

6. Make it useful. Baskets and boxes, while considered accessories in a room, are storage necessities. Use them to corral papers, remote controls, jewelry and any other odds and ends.

7. Think in triangles. If you’ve ever studied great painting or sculpture, then you know that many artists use a triangular composition to guide the viewer’s eye and make for a more dynamic composition. Do the same when you are styling. The best arrangement is a scalene triangle, in which all sides have different lengths. In this case, it translates into grouping three things — one small, one medium, and one large — together.

Mayhew, a “Today” show style expert and former magazine editor, is the author of “Flip! for Decorating.”

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Home Front chat: Join us Sept. 10 at 11 a.m., when journalist and TV personality Frances Schultz, author of “The Bee Cottage Story: How I Made a Muddle of Things and Decorated My Way Back to Happiness,” and staff writer Jura Koncius host a Q&A on decorating and household advice.

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