enumerate the procedure of adjusting valve clearance
Answer:
1.)Use a ring spanner to loosen the locknut and turn the screw clockwise to decrease the gap, and the opposite way to increase it.
2.)When the clearance is correct, hold the screw with a screwdriver while you tighten the locknut, then re-check the clearance.
3.)There may be a self-locking adjusting screw with no locknut.