During the darker days of winter your decor could change in your perception from cosy to gloomy, especially if you have used any of the bold colours currently on trend. I have a deep dark teal on my sitting room walls but luckily the room is double aspect so it's not too oppressive.
However the corners of the room can still disappear into the shadows, especially at dusk. If this happens in your living space I highly recommend placing lamps to banish the shadows and add light.
There's such a huge range of lamps available now from tall floor-standing designs to tiny clip on spotlights which can be used to uplight plants which I think looks especially effective.
Think about your current decor style and choose lamps which complement it. I have quite a traditional style so have some slim brass-coloured lamps with pleated shades in neutral colours. However I was very taken with some modern statement pieces spotted in a large store in London during a recent trip. Check out the range online, somewhere like Home Depot for inspiration.
Change your light bulbs. I have a gorgeous huge decorative lightbulb suspended over my staircase which looks lovely but is absolutely useless at providing any significant light! Always check the power of any bulbs you buy and make sure they are suitable for the space. You don't want a dim bathroom if you are shaving or applying makeup.
I have "smart" bulbs which are connected to the internet and my smart home system so I can not only change the brightness but also the warmth of the white shades and even the colour. You get set scenes so the bulbs dim when you are watching movies at home.
Bulbs and lamps are quite a cheap fix but if you want to make a significant difference to the light in your house you need to think about your glazing. The best time to do this is during home improvements like extensions or when replacing failing glazing.
Make the most of natural light with a glass atrium or Velux windows. New sliding patio doors will allow more sunlight to enter your room too. Avoid heavy drapes and if you are not overlooked, don't hang net or voile curtains. They might look pretty but they block out a lot of light, especially if even slightly dusty. And they do seem to catch every little speck of dust!
In the evening you can add light with candles which can give a lovely light, especially on a table if you have friends for dinner. If you are renting and not allowed to have real candles, pick up some battery operated ones - some even come with a remote control and can be very effective. If you do use real candles make absolutely sure you blow them out completely before going to bed or going out.
Finally adding mirrors in strategic spots can increase the amount of light in your home- keep them sparkling clean and they will reflect light into your rooms.