There are many ways of initiation an awereness campaign. We can categorize them in two groups: free and paid.
Those actions do not require any money from you. However, they are more costly in terms of your engagement and work you need to do, so they could work. Things which you can do for free include:
1. Spreading the word on social media (Facebook, Twitter, Instagram, Pinterest, Google+, tumblr, etc.). You can use your friends network in order to try and make your posts seen by more people, by asking for likes, shares and similar.
2. Making a home made video and sharing it on the above. You just need a phone which can record videos ;)
3. Preparing some kind of self-made leaflets or posters and putting them up in your school or other places where they could be seen by your potenstial target group.
There are also paid options, they normally require less effort but they cost money.
1. Paid ads on the Internet. You can use either Facebook or just Google and advertise your campaign using special keywords (those words which are specific for your campaign) and setting your target group (people to whom your ad should be delivered)
2. Any kind on adverstisment in the classic media (TV, newspapers, magazines, radio, etc.).
Those are just a few examples of the things that you could actually do. I hope it will encourage you to search also for other possibilities :)