Light your tea light and place a piece of wax in the spoon and hold the spoon over the tea light until the wax melts. Pour the wax onto the desired surface and quickly spread the wax in circular motions till it's the size of your stamp (be sure to be quick, the wax hardens quickly). Gently press the stamp onto the hot wax.
You could use a bigger kitchen steel spoon and more pieces of wax as well if you're more comfortable with that. To clean your spoon - soak it in hot water.