Things that can help reduce sediment:
- get a decent boil to get some hot break.
- use irish moss or worfloc in the boil.
- cool quick to get some cold break.
- if you strain hops, do not rinse with hot water.
- leave beer in fermenter for a few weeks. The longer, the clearer the beer will be. A couple of months will not hurt the beer, but hoppy beers like to be bottled sooner than later.
- dark grains tend to stay in suspension longer. Leaving them to settle longer will reduce sediment and make the beer smoother.
- use felatin to drop some of the yeast.
- cold crash the fermenter before bottling
- do not disturb the cake when bottling. I find this is easier by using a secondary, as the sediment/cake in a secondary is very much less than in the primary, making it easier to get as much beer out as you can, with very little disturbance of the sediment.
I've never cold crashed, but do most of the others, and get clear beer and very little sediment in the bottle.