• Warm up by doing three big, slow arm circles in each direction to prime your shoulder joints.
• Do 25 reps of the Upright Row, which targets shoulders, upper back, and abs: Make a fist with each hand and start with hands near hips, palms facing you; bring both fists up to armpits, skimming torso with knuckles and keeping elbows bent out to sides higher than hands throughout movement; squeeze shoulder blades and upper-back muscles together to draw elbows back, raising fists to shoulder height; lower hands to start.
• Do 25 reps of the Chest Press, which targets chest, biceps, and abs: Make a fist with each hand, arms straight down by sides, palms forward; keeping shoulders down and back, contract abs and lift both arms straight in front of you, palms up, to press pinkies together at shoulder height; squeeze chest, then lower arms to start.
• Do 25 reps of the Lateral Press, which targets shoulders and triceps: Make a fist with each hand and raise elbows out to sides at shoulder height, fists at armpits, palms facing in; keeping elbows fixed at shoulder height, slowly swing fists down until they're perpendicular to ground and then out, ending with arms extended straight out to sides, palms facing behind you; bend elbows to return to start.
• Do 25 reps of the One-Arm Reverse Fly, which targets your shoulders: place left hand on left hip and, making a fist with right hand, rest it on top of left hand, palm facing in; draw shoulders down and back; with right elbow slightly bent, lift right arm on a diagonal to right and up, ending with right hand slightly higher than right shoulder, palm forward; lower right arm to return to start; repeat with other arm.

If I start now, I should look better in my sleeveless tops by the time the weather is warm enough to pull them out of the closet!