You can create an alternative identity and use that for everything you can. Use paypal and non reloadable prepaid credit cards to pay for all services under your identity so they can't be tracked as you. Create all social networking accounts under this identity. Never associate with any of your personal interests, frequent websites you previously used, or interact with any usernames that you had contact with under any other identities. Never share your identity with anyone IRL. It is very easy for them to say something foolish and compromise everything you have been working on. Avoid keeping regular hours online because it can reveal your work schedule and clues as to what your job is.
On the technical side of things, you should use a VPN. Make sure it is from a reputable company and paid, because free VPNs will sell data on you. You can use one on your own server but if you do this you cannot be "anonymous" because all activity will track back to your alternative identity. Try using a popular VPN and change exit locations regularly. Make sure that you use a kill switch in case your VPN fails. Create a separate user on all of your computers for your identity.
Make up interests and a biography for your identity. You must become this person.
Never assume that you are completely anonymous. If you piss people off and make them really want to find you, they'll find a way. Somebody can always drop a payload on you or social engineer you into installing an app.
Big Data will be tracking you, but they'll be tracking a fictional identity.