Browse the Internet through a Virtual Private Network (VPN).
Never use a free VPN provider.
VPNs do not protect against all ways to determine your identity.
Remember that you are not anonymous to your VPN provider.
Use Tor to hide your identity online when you cannot trust any VPN provider.
Use the Tor Browser Bundle.
Use Tor Bridge relays when you need to hide your Tor connection from your ISP.
Use Tor hidden services (".onion" services) whenever possible.
Be aware of Tor's limitations.