I have a love/hate relationship with Outlook. It's the required email client at work and because it interfaces with so much of what we do, it's pretty much essential. However, it consumes a lot of overhead for a mail client, and at times it can be finicky in its behavior. But since I've been using Outlook for years and years now, I've developed a few tricks with it, usually by reading a tip here or a tip there and testing them out, to make it more efficient for me so I can be more productive.
Inbox Zero Concept - Subfolders for Action, Waiting For, Hold
Taking a lesson from the numerous recommendations for those striving to get to Inbox Zero, I try to make a determination of what to do with an email when I first process it. This leads to a few subfolders:
If it's an email I know I have an action on that I can't get to right now, I drop it in the @Action subfolder. If it's a case where I have an email (usually one I've sent) where I'm waiting on a reply or an action from someone else, I drop it in the @WaitingFor sub-folder. If it's something that I know I'll need soon, but not right now, I'll drop it into the Hold folder. The @ in front of Action and WaitingFor not only catch my attention, it ensures that Action and WaitingFor are sorted before Hold. And that's the way I want it. Now it is important to check those folders regularly. I typically check the @Action at the start of the day and after lunch, while I check the @WaitingFor and Hold folders usually once a day.
Arranging Messages by Conversation
I'll admit this one took some getting used to. However, I saw how effective it was for a network engineer/architect that I have a great deal of respect for who always is extremely productive. He processed about as many emails as I do and this was one of his tricks to managing them. If you've never seen this, you'll need to go View | Arrange By | Conversation, like so:
Most folks I know, which previously included myself, have conversations in the normal view where things are sorted by date. The problem with this is when you've got to track down the entire thread, especially if you have efficient "snippers" for coworkers or are yourself one. I can be one and I have coworkers that are, too. That means the latest message on a thread, sorry conversation, may not contain all the details you want. However, if you have them arranged by conversation, they stay together and all is well, at least with your message arrangement. It does mean your inbox view looks something like this, though:
Note that the last line there shows there are 2 items (2 messages) in that conversation. If I click the down arrow, I see the entire set of emails and can read through them as needed. It also makes this very easy to move and/or delete an entire conversation. Now because I use conversation view, I may break Inbox Zero here. I'll leave conversations for tasks I'm actively working on in the Inbox folder because I'm tracking them in this manner. Outlook doesn't group them up across all sub-folders. Maybe there's a way to do that, but thus far it hasn't been inefficient enough for me to look for a solution.
Using Categories in Calendar
I used to have a calendar view where I didn't categorize meetings and appointments. At a glance I didn't have any clue how my time would be spent that day. Then I decided to categorize and use colors to differentiate the different categories. My current category list looks like so:
The colors are key because some events are recurring and if I see them on a certain day at a certain spot on my calendar then simply clicking on that day, I see them, it jogs my mind, and I actually don't even have to look closer. However, for those events that I do, the colors help, too. For instance, here's how a particular Wednesday looked on my calendar recently:
You can classify something with multiple categories but the way Outlook handles that is whatever the most recent categorization is the primary color of the block. In the lower right hand corner there will be squares with the colors of the other categories. That doesn't do anything for me, so whatever the primary category is determines what I set for a given appointment. Just looking at this day, I can quickly see I have a community appointment, a training appointment, and a ministry appointment. As a result, without digging any further, I have a rough idea of how my day will shape up, not including work tasks. So the calendar provides a framework to help me with my day and the color categorization helps fill in some of that framework.
One other thing to note is that I do have a mix of work and non-work appointments on this calendar. That is by design. When I go to look at my calendar, whether through Outlook or my work issued mobile device, I want to see all my appointments in one place. It is part of the system I use to track what I need to be doing. Some would argue that you shouldn't mix these things up, but I have found it less productive and potentially confusing to not do so.