Cottage style decorating is an extremely broad category. It gives you a great deal of freedom when selecting the colors, textures, furnishings and fittings.
In fact, it's hard to define the style. Most people's cottage style is what they end up with after they've used all the hand-me-downs and family heirlooms.
This doesn't mean the end result is a mess - far from it! The main requirement is that you have the correct property, or if not the property, then the right sized room.
Cottages by definition are small places; it wouldn't be sensible to try for cottage style decorating in a ballroom.
Your cottage color scheme
No matter how many bits and pieces you include in your cottage style decorating, you'll need to have some sort of unifying color scheme.
There's a great deal of freedom here. If you like a particular style such as English cottage, then you'll be drawn to the soft colors of roses - reds, pinks and greens. A Rustic style would suggest browns, golds, and rusts.
Your own style
If you don't have a particular style in mind, your situation might suggest colors to use. You may have a garden where certain colors predominate, so those could be your inspiration.
Or simply select your colors from a palette of your liking, but make sure they have that slightly old fashioned look. You could also use a particular item, such as an old painted dresser or a rug, for inspiration.
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The Shortcut to Perfect Paint Colors - Paint Color Cheat Sheets
Have you thought about these features?
Here the key is to keep window treatments soft and light. Don't use heavy interlined curtains, but try to achieve a softer and more delicate effect. You can use frills and valances, and these can actually create a dreamy look.
If your windows are very small, think about using voiles or lace. Although lace can be quite expensive, you'll only need a small amount.
You can use almost any sort of furniture for your cottage interior as long as it's not too big and imposing. If the color of a piece doesn't match your scheme, then paint or stain it. If that's not possible, and it's a table or chair, then cover it with fabric.
Cottage decorating style looks best when there are lots of lamps around. Ceilings in cottages are often low, and overhead lighting might not be practical. Use fabric shades on table lamps, and you'll get a warm and cozy feel to your room. Or get a floor standing uplighter lamp which gives adjustable background lighting.
Cottage style decorating is informal, so fabric patterns should reflect this. Small prints of flowers and plants, stripes or checks, all of these working together will help in giving the look you want.
Walls can be painted in colors to tone with fabrics, or papered in a sympathetic pattern. Small cottage style decorating can be more 'busy' than other decorating styles, as long as there's a continuity of effect.
Cottage style decorating is the ideal situation for uneven bare floorboards, painted or stained floors, or tiles. The suggestion is often made that you shouldn't use wall to wall carpets in a cottage. But I've often used then when designing schemes for clients, because they give a warm and intimate feel to a room.
You can use old family items, or buy accessories from antique shops and flea markets. When you're on vacation you often see things you'd like, and with a bit of thought you can use them as part of your decor.
Also, try and make use of old bits and pieces you have tucked away. A small table you hid in the garage when cleaned up could look great in a corner of the room. Or make a cloth to cover it, and place a lamp on it.
Old wood towel rails will give character to your bathroom instead of the usual chrome, and the same can be done with wood shelves instead of glass ones.
Above all, have fun with your cottage style decorating!