You'll need a sharp knife (boning, paring, or chef's knives will work fine) and a cutting board. Place your chicken thigh on the board skin-side down and find the bone that runs along the length of the piece. Run your knife along the length of it to expose the bone underneath the meat. Using your fingers, separate the meat from the bone as best as you can. Angle your knife towards the bone and slice down both sides in an effort to dig the bone out a bit more, trying to scrape along the bone so no meat remains attached. Then, slice around and below one end of the bone to release it completely from the meat and pull the bone up, making a few more cuts to release the other end. Remember to save your bones in a freezer bag for homemade slow cooker chicken stock later!