If you commonly retain emails in your inbox so that you can refer back to them, it’s easy to end up with an unmanageable quantity of email, and as the number increases, it becomes more difficult to find specific email when you need it. You can simplify managing and organizing your inbox by creating subfolders and rules that automatically place email from specific senders into them.

To create a subfolder:

Right click on the Inbox folder and then select “New Folder.” The “Create New Folder” dialog box appears.

In the “Name” text box, type a name for the folder

In the “Folder contains” list, confirm that Mail and Post Items is selected.

In the “Select where to place the folder” list, select Inbox, or select a subfolder of the Inbox, if desired.

Click “OK.” If the Inbox's subfolders don't appear, click the plus sign next to the Inbox to display them.

To create a message handling rule that automatically places email into a subfolder:

1. Select Tools > Rules and Alerts.
2. Click “New Rule.”
3. Select “Start creating a rule from a template,” if not already selected.
4. Select “Move messages from someone to a folder,” and then click “Next.”
5. Under “Step 2: edit the rule description”, click the “people or distribution list” hyperlink.
6. Select someone from the contact list or simply type in the email address in the “From” box, and then click “OK.”
7. Click the “specified” folder hyperlink, select the client's subfolder, and then click “OK.”
8. Click “Finish”

And lastly, if you create very many rules, you will want to back them up so you don’t have to recreate them in case of a system failure or move to a new system. This is pretty easy and quick. 

1. Select Tools > Rules and Alerts.
2. Select “Options.”
3. Select “Export Rules.”
4. Select a location to save your rules, and type in a name for them.
5. Click “Save” and then “OK” to exit.