Add Brightly Colored Throw Pillows and Scented Candles

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Bring some spring into your living space by adding some brightly colored throw pillows and scented candles. When selecting candles, try to avoid smells that are reminiscent of winter such as cinnamon or vanilla . Go for scents that remind you of warm weather: florals and "ocean scents" are a nice pick-me-up.
Display Fresh Flowers

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Absolutely nothing says cheery like fresh flowers, and the more the merrier. Purchase summery bouquets of cut flowers at the grocery store and separate them into several separate small vases . Many dollar and discount stores carry these small brightly colored glass vases at very reasonable prices.
Keep the Bedroom Bright

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Getting a good nights sleep is always important, but even more so when you are feeling blue. There is no need to give rooms a complete makeover to give them some summery style. Add some brightly colored accessories in different fabrics to bland bedrooms to turn them into an at home retreat. (Don`t forget the flowers and candles in the bedroom)
Grow Your Own Herbs

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Diet also plays an important part in banishing winter blues. One easy way to add extra nutrition and a little bit of summer into meals is to grow your own herbs. Many herbs produce pretty flowers and growing them indoors will add a nice fragrance to your home.
Don't Forget The Bathroom

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Breath new life into your bathroom with a little paint and accessories. Fill it with fresh or dried flowers, candles, potpourri, fluffy new towels and anything else that makes you feel good. Replace blinds with light colored airy curtains, and you have to perfect place to soak away the blues.
Lighting

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Just because there is not as much natural light during the winter months doesn`t mean that you have to go without. Replace regular lightbulbs with bulbs that produce simulated natural light. They help to reduce eye fatigue and promote a better sense of well being.