Currently in the process of trying to validate a social networking app for college students. Am I headed in the right direction to keep costs low?

Currently I do not have a working service/product, but have a clear focus as to what I want the application to be. Since my focus is college students I plan on taking the marketing strategies I have chosen to follow to my college campus and other local college campuses in my area. Also by the help of old high school friends that are at other college campuses. By the way I have a full business plan. Before this I am planning on creating a large amount of stickers, flyers, contacting college newspapers, new stations, posting on social media and then have them directed to the landing page that I am currently creating. Since I want to keep costs low is this a decent way of getting it out? On this landing page I am going to encourage them to sign up for the newsletter to get somewhat of an idea of how many people are actually interested. Im doing this portion to validate my idea and attract potential investors when I pitch the idea. I feel like I am headed in the right direction, but somewhat scatterbrained because it's so much. I am not an app developer whatsoever so searching a CTO is also on the to-do list. So am I headed in the right direction? Would love to speak with someone if possible. Thanks!