What I don’t like is the interconnectedness of my computers. I have a iPad and a Win 10 machine. I surf for a new tire on my iPad, which does not have Facebook on it. And then I go to my Win machine and there are ads fore tires, including in my Facebook stream.
Mostly just for the challenge, and partly because it creeps me out, I try to avoid what you describe. It's really pretty simple:
Never log on to anything unless you have to. Don't set web sites like Amazon to "remember me."
Set your browser to clear all cookies at close - then close it between sessions.
Do all your searching on Amazon without logging on. When you find what you want, copy the first part of the address (only the part before the "/ref") to the clip board, close the browser, open back up, log on, then paste the saved address. You can buy the item without leaving behind any search history. It also means they can't change the price based on your history, without you knowing.
Install a browser add-on like "Ghostery" which blocks trackers. Basically every web page you open has a slew of tiny, one-pixel images on it, each on a different server. Your browser dutifully requests that image from each server, sending along a bunch of "header" information about your environment, such as browser type, any cookies it's saved and your IP address. Each of those servers belongs to a company whose mission is to track your every movement.
Use an ad-block browser or browser add-on.
Never use your Google or Facebook or other such account to sign on to some other web site. No need to link everything together for them!
Never click on all those social media links on third-party sites, and try to convince your friends and relatives not to "tag" you too much, and especially not to type in your e-mail address on those links to "send this to a friend." If you want to share something with me, send me an e-mail or text with the link, don't tell some web site to do it for you.
There's a lot more you can do, but I try to stop short of tin-foil-hat territory. It's really just a game to me.