The success rate of most propaganda campaigns is dubious.
There have been some very smart and successful ones, e.g. "It's Okay To Be White" and the more old-school "Diversity Is Code For White Genocide". However, most propaganda campaigns meet with little apparent success. Some poorly-planned ones even have a *negative* effect; propaganda posters featuring swastikas or slurs play directly into the narrative of "evil whites attacking innocent minorities", which simply drives normies deeper into delusion and self-guilt.
Practically everyone misunderstands how propaganda works. The average attitude on here is if you put up a message you agree with, people will see it and agree with it too. This disregards that the vast majority of people simply aren't mentally ready to handle the ideas we deal with on a daily basis. Many do not even realize that white people are under attack.
However, there is an incredibly easy solution to this. Rather than design your own propaganda, which may or may not work, *print off examples of Leftist anti-white sentiment* and post them around without commentary. When confronted with these, the average person will naturally feel threatened and actually begin to redpill themselves.
What's great about this is that rather than simply stating that white people are under threat, you are actively demonstrating it through prominent real-world examples of anti-whiteness. Show, don't tell. And the best part about this is that you can't get in trouble. All you're doing is posting articles from respectable news organizations, pictures of culturally-aware works of art, and photos from progressive and antifascist demonstrations. What could be wrong with that?