Join a project
Time to start searching.
Is there a citizen cybescience project out there that fits your interests? If so, join it. Even if you can't find the perfect fit, try joining something that looks interesting, just to get a feel for how these sorts of projects work.
Here's some places to start looking:
BOINC offers a lot of projects that involve volunteer computing, everything from climate modelling to quantum chemistry. P2PU already has a challenge set up to get you involved in BOINC, called Become a Citizen Scientist. Try it!
Zooniverse offers a range of exciting projects that involve volunteer thinking. Everything from cataloguing galaxies to digitizing old naval logbooks.
PyBossa is a new development for volunteer thinking, and allows you to build your own volunteer thinking projects in an easy, modular way. It also has a bunch of interesting demo projects. Check it out!
Still not finding what you want? There are some great portals to citizen science projects of all shapes and sizes. We recommend SciStarter as a good starting point.