How to get the most power efficiency of solar panels?
How to use solar panels efficiently.

a) Get all the light on them you can.

Point them at the sun.
Be outdoors.
Keep them clean.
Report their generation levels when the sun is shining, rather than when it's cloudy.

b) Load them with the correct load

Use a MPPT (Maximum Power Point Tracking) converter. This adjusts the amount of current it takes from the panel, and measures how much power it's drawing. It then makes a small adjustment, measures again, and keeps which of the two settings produced the most power. It then keeps this up indefinitely. 

As the panels' output varies during the day, it will track to maximise the amount of power it's drawing, as long as it has somewhere to send the power to. Common power sinks tend to be a battery in need of charging, an inverter back-feeding the mains, or maybe a water heater or bunch of light bulbs for experimental purposes. 

The power sink must be capable of absorbing the maximum power the panel+MPPT can generate, otherwise damage could occur, or the MPPT will adjust down giving you pessimistic metered power.