1. Purchasing furniture before measuring a room
In their excitement, many homeowners buy furnishings before taking possession of their new homes. However, when the furniture arrives, often it doesn’t fit through the door or it’s too long or deep for the room. Rather than making buying decisions based solely on a floor plan, live in your space for a while. You’ll make better choices.

2. Highlighting wimpy trim and moulding
Everyone thinks they have to highlight baseboards and trim by painting them white. But if your trim is 3½ inches or smaller, paint it the same colour as the wall so it blends in; otherwise, you’ll end up with a racing-stripe effect around the
room. Another great tip: Paint your baseboards, walls and crown moulding the same colour to make the ceiling feel higher.

3. Going without a headboard
The head of the bed is the focal point of any bedroom, but many people tend to overlook the headboard. If you prefer not to have one, add interest with eye-catching artwork or a decorative tapestry, or paint the wall behind the bed a dramatic colour.

4. Buying area rugs that are too small
An area rug should allow for a 12- to 16-inch border of flooring around a room’s perimeter; anything more and the rug will look insignificant. Remember: The front legs of your furniture should sit on the area rug, so the rug doesn’t appear to float in the middle of the room.

5. Trying to hide your TV
If watching television is the primary activity done in your living room, it’s silly not to embrace it. Work the screen into your decorating scheme by adding touches of black or dark grey elsewhere in the room, with accessories such as picture frames, lamp shades, curtain rods and
side tables.

6. Choosing paint colours first
You’ll drive yourself crazy trying to find a bedspread that perfectly matches the shade of smoky plum you already painted the bedroom walls. Instead, invest in the bedspread you’ve fallen for, and let one of the colours from its pattern inform your paint colour. Remember: Although there are thousands of paint colours on the market, there are only a handful of fabrics that will really speak to you.

7. Having more than one focal point in a room
Every space needs a focal point, but most people never figure out where those focal points actually are. In the living room, the focal point is either the TV, fireplace or window view – whichever one you enjoy most. In the bedroom, it’s the headboard; in the bathroom, the vanity area.
8. Being a slave to sets
Matchy-matchy furnishings sold as sets (think full bedroom suites with bedside tables, headboard and dresser) are a thing of the past. The key to the au courant eclectic look is to combine different pieces that play well together in terms of proportion, wood (or wood finish) and fabric. The furnishings in a room should feel like they belong together while also standing apart with unique personalities.

9. Hanging artwork too high
The bottom of a piece of art should sit eight to 10 inches above a piece of furniture, be it a headboard, sofa or credenza. In a hallway or stairwell, hang art so that the middle of the work is 66 inches from the floor or steps.

10. Not layering lighting
No matter how brightly it shines, a single light fixture in the family room ceiling isn’t going to cut it. Overhead lighting is just one layer in a decorator’s three-tiered approach to illumination. Each room should also have task lighting, such as a swing-arm lamp for reading, and ambient lighting, such as candlestick lamps, to add a bit of sparkle.

11. Displaying collectibles all over the house
Create big impact by grouping a collection of figurines on a table or family photos on one wall. Dotting them all around the house only creates a cluttered look.

12. Positioning furniture along the edges of a room
Try dividing a long, narrow room by using the two-to-one rule: Make two-thirds of your room the main seating area, and one-third a space for a desk, reading chair or piano. Don’t be afraid to show the back of a chair or sofa by using the piece to divide the room.

13. Decorating around a piece you don’t love
Chances are, if you don’t like it today, you won’t like it tomorrow. Don’t continue to invest in decor and accessories to match the item; get rid of it, have it refinished or store it in the garage or basement.

14. Doing it in a day
When you shop for an entire room’s worth of decor all at once, it looks like you did it in a day: Everything matches, as if you purchased the display from a store window. Take your time and let your vision, goals, budget and timeline guide a gradual decorating process. It’s fun to build the look of a room!
15. Hanging cheap drapes
Although inexpensive tab-top drapes may be perfect for college dorms and teenagers’ rooms, casual window fashions are rarely a suitable investment for an elegant living or dining room. Custom-fit draperies will never go out of style.

16. Getting the scale wrong
Most people buy sofas that are too large, and rugs and other furnishings that are too small for the rooms they’re in. Balancing the scale of furnishings is an art; a large armoire in a small room isn’t necessarily a bad thing – if you create balance with a dark wall colour, oversize framed art and rich carpets.

17. Choosing trendy fabrics for long-term furnishings
Custom sofas, chairs, headboards and draperies should last many years. Opting for a trendy colour of fabric will quickly make these pieces look (and feel) outdated. Instead, choose colours that are a shade lighter or darker than your more classic wall colour, so the furnishings work well together and maintain timeless appeal.

18. Collecting too much stuff
Learning to edit a room is a huge lesson. The easiest way to do this is to dress a room completely and then take away 30 percent of the accessories, such as candles, picture frames and knick-knacks. That will leave room to add items as the decor develops over time.

19. Buying too many small accessories
Forgoing trendy accessories for a year or two could save you enough money to buy one substantial piece of furniture you’ll have forever.

20. Creating monochromatic humdrum
Homeowners often play it too safe and create beige-on-beige interiors that lack excitement. Using one colour for fabrics and walls doesn’t have to be boring; create drama by choosing lighter and darker hues of the same colour.
21. Mixing too many wood tones
This rule is a simple one: Introduce no more than three different wood stains in a room (that includes flooring, cabinetry and furnishings). If you have pieces in different stains, refinish some of them in order to create a cohesive look.

22. Hanging oversize family portraits in main living spaces
Save all those large framed  family, school and wedding photographs  for the upstairs hallway, home office and den.

23. Choosing the wrong hue
People often know what colour they want, but don’t pick the proper hue (lightness or darkness). Try this good rule of thumb: Lighter on the top, darker on the bottom. Walls should be a lighter hue than the floor, and the ceiling should be lighter still.

24. Skimping (or overdoing it) on toss cushions
My simple formula is one toss cushion for every two feet of seating. No more, no less.

25. Buying a chandelier that’s too small
Multiply the width of the room (in feet) by two to find the diameter (in inches) of chandelier that will work in that particular room. For example, if the width of your room is 12 feet, then your chandelier should be about 24 inches in diameter.

This story was originally titled "The 25 Worst Decorating Mistakes (and how to avoid them)" in the November 2012 issue. Subscribe to Canadian Living today and never miss an issue!