What happens next?

How to light a water heater
Check the pilot light.
You will probably need to remove a small panel, called an access panel, at the bottom of the tank in order to see whether the pilot light is actually out. If you do not see a small flame burning, then your pilot light has gone out.

Choices: - If you can't see small red sparks coming from the pilot light at the bottom of the tank, then your pilot light is likely either being burnt or not lit. Open the tank's set of panels.. - If you have a newer water heater, it is possible that your panel is not removable and that you view your pilot light through glass. In this case, if you cannot see a flame burning through the glass, then your pilot light is out.. - If there is a large, small flame burning through the bottom window, however, then your pilot light is probably out. Find the factory-rated pilot light and oil tank units.. - Make sure that the shutoff valve will turn off. If it does not, then you have to replace it..
If you have a newer water heater, it is possible that your panel is not removable and that you view your pilot light through glass. In this case, if you cannot see a flame burning through the glass, then your pilot light is out.