This page has advice about how to force hyacinths and information about the varieties I have used in recent years.
There are four main steps to successfully forcing hyacinths for Christmas/early-January, in summary:
1. Order bulbs early, specifying those "prepared for indoor forcing". Some bulb companies give a discount for orders received before the end of June but certainly as early as possible to ensure availability of the varieties you want. You can also buy prepared bulbs in August at garden centres. Some years the prepared bulbs seem to sell out faster than others. This year I was still able to buy a bulb for a last minute ebay vase in December.
2. Prepare the vases in September by putting the bulb in the top and filling it with water to about 1 cm below the bulb, basically as high as you can without touching the bulb.
3. Put the vases in a cool dark environment. A cool cellar is ideal but a fridge would work. (I tried a fridge this year but the bulbs in the fridge were very slow to develop. Based on this experience I don't think it's necessary unless the weather is very warm in the autumn.)
4. Check the vases regularly for 3 months, topping up the water as required.
5. Bring the vases out into the light in December or January - but only after the flower is fully out of the bulb. I was able to bring a number of vases out of the cellar about December 15th and then some a week later and some a week later still. The last 10 vases are still there (as of December 30th) so you need to judge for yourself depending on the bulb's development.
Ready to come into the light. The bulge of the flower is out of the bulb, left.
Keys to forcing success
* dark, cool environment
* time left in the dark until the flower is out of the bulb
Just before Christmas/end of December, the buds are ready to burst into bloom, above.
August/September just getting bulbs and vases ready to go into the cellar, below.