You're never 100% anonymous over the Internet. You'll always leave some trace or clue somewhere for someone with the right resources and skills to follow.
Some Tips For Better Anonymity
- Install a VPN client and use it when you want to keep your internet activity private from your ISP.
- Consider using the Tor browser instead of your regular browser for added anonymity and privacy.
- If you're tech savvy or fancy a challenge then give Qubes OS a try. It's the operating system Edward (Ex CIA) Snowden recommends.
- Trust nobody. Don't share personal information with others, no matter how nice or honest they seem.
Recommended Privacy and Anonymity Tools
ProtonVPN: You can download and use the software for free. Giving you a limited but very secure connection when needed. Use it when accessing public networks or checking your ProtonMail etc. A Virtual Private Network lets you connect to external websites and other cloud services via a secure connection. Anyone trying to intercept the traffic between your computer and the destination server will only see encrypted data.
ProtonMail: Simply put, it's email with encryption built-in. You can register and use it anonymously, which makes it a great choice for whistle blowers, freelance journalists and hacktivists alike. Your inbox, sent items, drafts folders etc are all encrypted and can only be accessed with your decryption key, meaning that even if someone hacked your account, without the encryption key, they will just see lots of encrypted text. The only drawback to encrypted email in my experience, is that both you and your recipient must be using an encrypted email service for it to be secure. Alternatives to ProtonMail are: Tutanota (Generous 1GB inbox, more than ProtonMails) and StartMail (No FREE accounts).
Tor: Tor offers you both the ability to browse the Surface Web and Deep Web anonymously, and even host your own hidden (website) service. The Surface Web is anything that can be indexed by regular search engines like Google. The Deep Web websites are those sites that can only be accessed if you know the server IP or private domain name (search engines are oblivious to their existence), Tor is also used to access .onion websites, the Darknet (slightly deeper and more hyped than the Deep Web). I highly recommend using Tor for all your browsing.
Qubes OS: Qubes is a Linux operating distro built with anonymity and privacy in mind. In short, Qubes OS can be configured to run apps in isolated areas of memory, called Qubes. You can even set up your email client to create single-use disposable Qube for opening attachments. Which means, isolating any potential security risks to that single Qube, firewalling it off from the rest of the system.
Other websites worth checking out:
https://www.privacytools.io/: Encryption against global mass surveillance.