how to install outlet or switch box between 2 closely spaced wood studs?

[mstudio]

Depending on what sort of box you are using, you can use screws instead of nails. Very easy to run a few screws on an angle. You can also cut a short piece of 2x4 to fit flat between the two studs and screw a box through the back into the short piece of wood.

There are plastic boxes available that are legal in most places now, they have a nail already in it on an angle to easily hammer into the stud.