I've bought nicely patterned sheets (think Laura Ashley prints and polka dots) and cut them and sewed and used them as curtain material.You can even have matching bedding and curtsins!

You can also check thrift stores (Goodwill, Salvation Army) for curtains/drapes, or fabric or sheets you can use to make some.

I just got two thermal-backed panels at Big Lots for $15 (regularly $28 at Wal-mart) each for a 40"x84" panel. These are going under my Levelor shades on simple, inexpensive tension rods, to keep out the heat and light (west windows), and they will help keep out the cold in the winter. They are a nice golden-beige linen-look (similar to my shades), but they came in other colors as well. Big Lots and Tuesday Morning always have nice curtains/drapes, as well as shades.

What you get depends on personal taste and budget. If you like to let the light in, you may want one layer of sheers or lace curtains, topped with a heavier fabric to close at night, or to keep heat/cold out. Personally, I have all my windows covered with energy efficient Levolor (honeycomb-style) shades.

The link below may give you some ideas. Often the hardware for hanging curtains/windows is very expensive, so keep that in mind when choosing.

-Grainlady

Here is a link that might be useful: Do It Yourself Window Treatments

I have the same panels as Grainlady. They do keep out much of the light. Purchased in March after most of our cold weather. If you watch Big Lots they go on sale for $10 about every 4 months. I also like Tuesday Morning but what I want they never have a complete set but if your window is small one panel is all you need.

You do need to decide what you want the curtains to do. If they are to lessen the heat and cold coming through the windows use the thermal panels but top with a scarf or heavy material because much of the temperature will find a way around the curtains unless blocked.

Watch the fabric stores for cheap material. Stepdaughter found large pieces of Organza for her windows from a bridal company. Keeps cold out better than curtains. Right now the back to school sales will be having extra long single sheets for $5 or so. Many are not completely sewn at the top and all you need to do is put a rod through them.

Check out Bed, Bath and Beyond when they have clearance sales. My DIL and I were in there not too long ago and she bought thermal backed drapes for her dining room for under 14 dollars for a a 5 foot wide window.

Decorating on the cheap can be done but you have to plan ahead and use the sales to your advantage.

I keep a note book with all my window sizes, a color chip of the paint for each room and the dimensions of the room with a floor plan in my purse.
I also keep a list of the different tables I have and the size clothes I need for them.
Saves me lots of time and money.

Grainlady, that link told me that I know nothing about window treatments. It will be a great link to review and to learn new terms from. Now to find out what a 'window seat' is I thought it was a place to sit and look out the window but no way to sit on the size given so must be something different. Great terms to check.

Right now, my Lowes is clearancing some really nice curtains for $5. See if yours has some.

Unless you are planning on moving in a year or so, why would you invest your money on cheap drapes? I did that in the past and was never happy with the results. Dye lots can vary from panel to panel, lenghts also are not consistant. I found by investing in good drapes they last much longer and look 100% better.

One reason to invest in cheap drapes/curtains is so you can change your decor and also amount of lighting you are letting in. If you have a window and want things light and airy looking for spring and summer then you would go for thin curtains. Then in the fall and winter you switch to more seasonal colors and thicker material. By purchasing cheap ones especially on sale you can change the mood of the room. The OP does not state if they rent or own. If renting no way would you want to pay a couple of thousand dollars for expensive drapes. Personally to pay over $100 for enough panels to cover my largest window makes me wince.

Cheap curtains are rarely lined and then you have the pfaff of trying to find linings to go on curtain hooks as well if you want to use them in Winter, to keep in heat.

In many towns in the UK, there are shops which buy and sell secondhand good quality curtains.

Cheap panels are good for a Summer look though, or to divide a room.

We have a store called Tuesday Morning that sells already thermal lined curtains for between $10-20. One of our box hardware stores sells thermal liner for drapes for $24, last months price. I will admit that most of these are to be hung on rods and not hung with hooks but you could also do the same.

It is always interesting to see differences from various countries and areas.