How to install? -----Fix the product with a right angle and make sure no shelter on the surface of solar panel.
How to use? ----The product is off before delivery in order to avoid discharging during transportation. You can activate it by using the pin or related button or tearing off the film. This is depend on different item, the activate way may differ.
What to do with the rainy day or Cloudy day? ----The outdoor solar light is waterproof. You don't need to worry about it. After fully charged, the capacity of battery can keep the LED working in several rainy/ cloudy days.
Why the charging efficiency is low in winter or cloudy day? -----Generally the sunlight standard is 1000kw/m2, in the winter or cloudy day, the sunlight intensity are much lower than standard so the charging efficiency is lower accordingly.