Quick warm-up to prime the shoulders for work.
Lead the motion from the shoulder and keep your arms long.
Arm circles are the simplest way to push blood into the shoulders and take the joint through a big, controlled range before you load it. Rotating forward with long arms sweeps the delts through flexion and rotation, gradually widening the circle so the joint warms into its full range rather than being thrown into it. Nobody builds a shoulder with circles alone, but as the first two minutes of an upper session they do exactly the job.
Around 15 to 20 forward circles, starting small and finishing big, is plenty. You are chasing warmth and smooth movement, not fatigue.
Painless clicking is common and usually just tendons gliding over structures as the joint moves. If the clicking comes with pain or pinching, shrink the circles and build range gradually.
Slow and controlled. Whipping your arms around does nothing for the joint, drawing deliberate circles that grow in size is what preps the shoulder for pressing and raises.
