Some useful tools I use:
GSx5 (or divide by half and add a zero ie 400kts = 200 0 = 2000) gives appr. a 3 degree profile.
It's very useful when you're using the 3-rule. If you're 1000' too high for instance, then, increase the V/S to your 3 degree rate and add another 200fpm for 5mins (or as req) and you'll get back on profile.
Learn to use the DME and track miles to go before you start depending on the automatics. On the boeing we have the progress page, if things are setup correctly it's very useful for perfect descents.
For a rough ToD wind calculation: divide the wind by three and use as a correction if above FL300. Works pretty accurately with low cost indexes on the 737NG, I don't know how slippery the bus is in comparison. For example: A headwind of 60kts = postpone your descent by 20nm. (60/3=20) It gives pretty much the same ToD as the one VNAV calculates. Interpolating works pretty good but VNAV does a slightly better job if you're still far out.
For slowing down, it's trial and error. It depends alot on the wind and the grossweight with the 737NG but I assume it's the same with the bus. In the beginning, try to slow down in level flight to get to know the energy management of the aircraft, note the distances and times needed, to make some mental rules of thumb and then start combining the slowing down while descending at the same time as you get more confident.
Comparing the DME/trackmiles with the metric altitude is also a fool proof method for us lazy people
just don't forget to subtract the elevation!