The thing about regular overhead pressing is that most people are really, REALLY bad at it and end up making it a standing incline press – plowing through their lower back and not hitting the shoulders as much as they'd like.
One exercise I like to use with clients is the legless or tall kneeling scrape the rack press. By kneeling on the ground you take the lower back out of the equation, which automatically makes it more challenging because it's harder to cheat. Moreover, because you're pressing INTO the rack you'll get more serratus activation and anterior core recruitment which will nudge you into a little more posterior pelvic tilt (better overall alignment).
I'll often have my clients perform a heavy-ish set of these for 6-8 reps, followed with a lighter dumbbell variation so they can really feel the delts work. Most guys have a hard time getting their delts to grow because they try to "muscle" everything and use too much body-English (bouncing around at unnecessary levels).
Follow the scrape-the-rack press with one of these two moves using light dumbbells, 10-20 pounds:
Dumbbell Lateral Raise: Shoot for 20-30 reps.
Ladder Dumbbell Lateral Raise: Do 5 reps, 5 second hold at top, 4 reps, 4 second hold at top, 3 reps, 3 second hold at top, 2 reps, 2 second hold at top, 1 rep.