1) i strongly recommend that you try to become more comfortable representing hands that you don't have when scare cards hit.
2) this is an especially powerful move when you have outs (e.g., boat and flush in this hand). players who are not totally brain-dead will be completely confused by this move and will start calling you down super light assuming that you're on draws all the time. as such, your monsters will get paid off quite a bit more often. additionally, when you move up and start playing against aggressive players, they'll try to rep a big hand when the scare card hits (e.g., flush or paired board on the river), and they'll be... well... betting into the nuts that you hold.
3) most players at these levels will let you know if you're betting into the nuts (usu. by raising immediately), so you'll usually have a good idea about where your at and what your approximate pot odds are to chase any draws you may have.
slightly more advanced tips
1) once you get a feel for who folds marginal hands and/or chases without proper odds and who doesn't, you can start making these kinds of flop and turn scarecard plays with air. you'll get a fold unless villain has a huge hand or a huge draw (relatively rare).
2) against players who chase a lot and/or can fold marginal hands (e.g., 2pr, baby flushes, flushes on paired boards, etc.) on the river, i also recommend you try to learn how to rep big hands on river scare cards (e.g., flushes and boats). you don't have to do it every time (in fact, you almost definitely shouldn't), but if you add it into the mix, you'll completely confuse your opponents.