Hey man,
clicking can mean some inflammation of the shoulder from overuse. Posture is very important when doing a press, ensuring your scapula are pulled back and you aren't bringing the bar down too low.
Use a smith, go very light (like 25 lbs per side), find the right bench position, use a safety bar at the chin level, and then do the exercise with 3 second negatives, pausing at the bottom, and then do the press. You'll be light enough to adjust your position as needed, but heavy enough to get some load through the tissue to make it respond.
If it's still painful, drop the exercise, focus on sub 90 deg front raises, laterals with cables and burn it out with sets of 12-15 2-3x/wk. Only when it's not painful or significant clicking can you go back to doing the press again, but following the advice I gave above to ensure you are doing it correctly.