Use an ad blocker (uBlock origin), keep your OS/Browser up to date. If you really want to get paranoid you can use NoScript or something like that (but you'll g

Use an ad blocker (uBlock origin), keep your OS/Browser up to date. If you really want to get paranoid you can use NoScript or something like that (but you'll give up some convenience). The main thing is to make sure you trust the things you're clicking on. If you have to visit websites or try programs you don't trust, some people have virtual machines specifically for those situations. They'll visit the site/open the program inside the VM, and if something sketchy does happen, it'll be contained within the VM and not infect the host OS (unless it's incredibly sophisticated malware that can break out of VMs--but very unlikely you'd be targeted by something like that).