It will depend on what you are trying to do.
If you are trying to run a command from a certain place and you have to navigate to there each time to run it the path command will help you.
For example if you keep all of your .bat files on the c: drive in a folder called bat
In the command window type path<enter>
Now type the EXACT thing that it just showed you and add at the end
If you just need it to go there each time you open the command prompt that can be set as well.
Right click it and hit properties
In the start in box set it to where ever you want it to begin.
Actually you can have several different command prompt shortcuts all leading to different places.