One of the best ways to control dust in a shop is to collect it at the source. The problem is the dust ports on many portable power tools don't often match the hose on my dust collector or shop vacuum. I used to cobble together a solution with duct tape, but a better solution is to make a custom-fit adapter.
The adapter is made from two layers of MDF. Trace the outline of the tool's fitting on a piece of MDF. Do the same for the hose. By gluing the two parts together, this technique guarantees a leak-free adapter.