One way to go about in writing this essay is to talk about how important it is to actually help someone.  Describing the value of service is a good way to develop an essay about helping someone.  It could be a feeling that you have when you help someone or a feeling that you get when someone helps you.  It might be good to talk about how society functions better when people help one another.  For example, when people are sitting outside of temples begging for food, it is good to sponsor a meal for them.  To be able to help them have food is something that makes others feel better and helps us feel better.  You might also consider using Swami Vivekananda's quote here:  "They alone live who live for others."  Being able to develop an essay from these points could prove to be quite persuasive and enlightening on the topic.
Helping is way in which someone come closer to each other. its not important to help only your friends or the people you know ,you should help other people also. if you will help someone you will feel very nice and when you will be in some trouble so then many people will be ready to help you .for example ,if your classmate needs copy to complete his / her work and he /she is not very close to you and is only a classmate so no problem, you should give your copy to him/her and when you will need  someones copy
he/she would be ready to give you so start helping others but do only that work that you know and can do.