I found great Answer for the Interior Design question about space.
There are numerous diy ideas and you will definitely find decorating tip here according to your taste and budget.
So the Best Answer:
Use Light Colors, Glass and Mirrors
Some of the tricks I’ve learned are to use light colors, mirrors to reflect light and make spaces look larger, and good lighting.
Glass top coffee and end tables visually expand your floor space. Upholstered pieces with legs also visually expand floor area.
Light (natural or otherwise) makes a room feel larger. Keep curtains open. Add more lamps.
Small pieces for small rooms
Big, dark pieces that sit right on the floor take up space and make your rooms look smaller. Go for sofas with clean lines and classic styling. No big huge rolled arms or overstuffed cushions, etc.
As for art, I’ve found that a few large pieces make more of a statement than a bunch of small pieces scattered around. Pare down accessories to “just enough” – don’t overdo, or you will end up with a cluttered look. Go for a few good looking pieces rather than dozens of little tiny stuff.
Get rid of clutter
Keep clutter to a minimum, and keep your place clean and picked up as much as possible. This will help so much. Keep windows sparkling clean, inside and out, and use lightweight or sheer fabrics for window treatments. Stay away from fancy swags and layers and “funeral parlor” looks. Keep it simple to let it natural light and give a feeling of airiness. Get rid of any furniture you don’t need. Organize everything in the room. Lack of clutter makes a room look much larger.
Double Duty Pieces is your new fave shopping goal
Opt for double duty pieces such as night stands or end tables with drawers, storage ottomans, chests and trunks, etc. Armoires keep televisions and electronic equipment out of sight.
Decorate with Satin fabric
Also, Satin finish paint will make the room look larger than Flat finish will since it bounces the light around a little more.
Some other tricks:
Furniture that is away from the wall
Contrary to what you might think, shoving all the furniture against the walls actually makes a room feel more cramped than pulling it into the room does.
This doesn’t mean you need to move all the furniture into the room, but if you move at least a few pieces into the room and away from the wall, the room will look bigger.
Furniture with clean lines makes a room feel larger. Ornate, fluffy furniture makes a room feel smaller.