I still consider myself quite a noob when it comes to being a DM, so I don't have three table tips to use in response to Hill Canton's GM Challenge Thingy. But there is one that I actually came up with all by myself that seems to work well.
Have players roll their own wandering monster checks.
Not necessarily the ones that happen every fixed number of turns, but the ones that come about as a result of their actions (or inaction).
For example, I usually have a failed open door check trigger a wandering monster check. This actually gives meaning to the failures, and makes it worthwhile to attempt to pick a lock when possible.
Also, the most important one is when the party is standing around in the dungeon while the players are debating a course of action at the table. More than just a little of this, and I ask them to roll a wandering monster check as a result of their bickering in the dungeon corridors.
This lets them know that they need to keep things moving both in game and out.