Recruit some of your peers and organize a day of grassroots door-to-door advocacy. Knock on people’s doors in your neighborhood to tell them about your cause and urge them to take action like voting, donating etc.
“Grassroots” means building support from the ground up. Basically it’s organizing a segment of the public and using their voice and power to pressure the decision-makers.
Handing out informative brochures or leaflets at your school or in your neighborhood can also be effective. This can be done at after school programs, church, extracurriculars
You could also organize a rally, demonstration or march. These are large gatherings of people to show support for, or opposition to, an issue. A large-scale rally or march can be a great way to demonstrate strength in numbers.