The previous answer is right, but in the practical sense, I'm concerned that if you use something labeled as an ammeter, it measures on the order of whole amperes, and you might not be able to detect the tiny current produced by a photovoltaic cell.
You would be better off with a ready-made voltmeter, unless this is a class where you're expected to use the equipment provided.
The open circuit voltage of a single crystalline silicon cell (the most common kind today) will be about 0.7 volt if cold, dropping in voltage considerable when warm. At maximum power, it might only be 0.4 volts. So if you have a 1k resistor in series with an ammeter, you'd only expect 0.4 mA (400 uA).
As far as current, the amount of current coming out of a photovoltaic cell is to the first order based on the intensity of light falling on it, NOT on the load resistance. So, in the practical sense, you can just put your ammeter straight across the photovoltaic cell, and measure the short circuit current. The current at maximum power will be about 10% less than this. Don't worry, it won't hurt the cell to short it out.