I'm using Visual Studio Code v1.24.0 on a Mac.
By default, the Panel will appear on the bottom (You can change the default as well. Please refer to @Forres' answer: Moving Panel in Visual Studio Code to right side)
Here's the bottom/right toggle button for VS Code Panel:
Once I click on this button, the Panel moves to the right.
Moving it back is a little tricky though. As you can see, some of the buttons are hidden. This is because the width of the panel when it's aligned right is too small. We need to expand the column to see all the buttons.
This is how it'll look upon expansion:
Now, if you want to move the Panel back to the bottom, click on the toggle bottom/top button again.