So far I've cancelled Netflix, Amazon, Norton, switched browsers to Vivaldi, switched email to Tutamail, and only purchased non-american items. I'm still going through the de-google list.
It's a lot of work, but I'm not knowingly giving the american economy a cent of my money.
Tell us what you're changing, maybe it'll give us some ideas.
Switch to Linux from Windows or MacOS, use a degoogled Android ROM such as GrapheneOS, pay using cash when in person and using Monero when buying online using sites like shopinbit (based in Europe) & others listed on sites like monerica and kycnot.me or cash/Monero bought gift cards, to avoid using US payment processors, in general using privacy respecting open source software.
Everyone should do this, not just as a way of hurting the American economy, but as a way of regaining freedom over their own data and privacy, including Americans. Your data and privacy is being sold as a commodity to brokers/advertisers and governments, particularly the US govt. You should use this opportunity to take back control over your own privacy and freedoms.