The Trump campaign aims to spend upwards of $1B during the 2020 election cycle. As explained in this Tiktok (also embedded below), here's how you can start chipping away dollar by dollar and click by click:
Make Trump's marketing team think you are a potential voter. Visit Trump's website, Facebook page, view his merchandise, etc.
Start clicking on any advertisements from the Trump campaign. Within an hour, these should start appearing on the websites you browse.
For bonus points, fill out the surveys that many of these advertisements link to. This will make him appear less favorable in 'polling data' that his campaign might try to use in future ads.
Repeat. Sources vary, but campaigns can pay up to $1 per click they receive on an ad. Because these marketing budgets are zero sum, each advertisement you see is an advertisement an actual Trump supporter will not see.
For more ways to ~troll Trump~ keep following along on this website and my Tiktok here.
Update: we've wasted $300K-700K of his budget
The above video went fairly viral and I estimate that as a group, we've wasted hundreds of thousands of dollars from Trump's marketing budget. Let's keep going. Showing my math/methodology in the TikTok below :)