If someone wants to promote his project then there are many ways to promote like here also people can promote but if they come up with an airdrop type like tweeting. In which there is a Social media .
 he has to work and he gives him some benefit or some profit from it, then all those who will work will also promote the program  And in a very good way, people will know it, so this method is the best for me, the rest are all the methods, the way advertising has become content, if people will create content and people will share, then your project will reach people.