Energy can be conserved in many ways. As a student you could easily adopt the following ways:
Do not leave electric appliances running when they are not being used. This would include putting off the lights and the air conditioning when you leave a room. Switching off your computer when you are not using it. Many appliances we use now can be put in a state of stand-by, but it should always be kept in mind that this only reduces the energy consumption. If you're not going to be back for a fairly long period of time, it is best to switch off the device entirely.
Try energy efficient ways of travel like using public transport. If you use a bus instead of your car you will save a lot of energy. If that is not an option, you could try car-pooling.
Always recycle instead of throwing away things as waste. It takes a much lesser amount of energy to produce plastic and metal when products containing them are recycled than when they are originally produced.
Many agencies now-a-days provide ratings that indicate how energy efficient appliances are. Choose those which are more efficient.