1
I rode my bicycle to the park.
Sign 'bicycle' using the alternating circular motion, then sign 'park'. You can emphasize the pedaling motion slightly to show the continuous action of riding.
2
My new bicycle is blue.
Sign 'my', 'new', then 'bicycle', followed by the sign for 'blue'. Keep the pedaling motion brief and contained, since you are referring to the noun (the object itself) rather than the action of riding.
3
Do you know how to ride a bicycle?
Raise your eyebrows to indicate a yes/no question. Sign 'you', 'know', 'how', and 'bicycle', maintaining eye contact with the person you are asking.