Step 1: Right click the "My Computer" icon on your desktop, 
or start up menu and click the properties tab.

Step 2: Click the advanced tab and then click the Environment 
Variables tab (should be at the bottom of the advanced page)

Step 3: Under system variables click "New" Add the variable 
name: "SUBLIME" and value of "C:\Program Files\Sublime Text 2\" 
(please note this could vary depending on your install location) 
Then click "Okay"

Step 4: Find the "Path" variable under the system variables, 
most likely you already have something in the "Path" value. 
You can click edit and add "%SUBLIME%" without the "", if you 
have something already in the "Path" just add a ";" before 
adding so it should look like this: "C:\whatever;%SUBLIME%"

Step 5: restart the command line, and type "sublime", this 
will launch the Sublime Text 2 editor.

Pro tip: if you want to shorten the sublime command you can 
rename your sublime.exe to subl.exe, restart command line and 
type "subl" this will now launch the text editor.