A couple tips...
Put the bottles in a dedicated closet for conditioning. I lay them on their sides...or...place them into crates. Crates make it easier to shake the bottles to keep the yeast suspended.
Try to keep a constant 80*F so the yeast will be more eager to work and try to use fresh yeast at bottling time. Also, a small starter of champagne or Belgian yeast can really speed up the process. Just don't forget they are there at that temp...getting a head start on carbornation is OK, but don't leave them more than two or three weeks as that can impact the flavour.
If you can't keep that temp, make or get a small heater with a thermostat. I made a small space heater using a couple power resistors bolted to a heatsink which has a shroud around it and an 80mm fan blowing air through. Hooked it up to a small timer circuit so I can adjust the duty cycle and hence temperature. I power this contraption with an old computer power supply. Works great.
Using these methods, all my strong Belgian beers (including a recent 11% tripel I made) usually carb in three weeks, though that doesn't mean they are done...far from it.