The Best Exercises for Abs at Home, According to an Expert Personal Trainer  

Lay on your back with your knees bent 90 degrees and feet up. Return to the starting position with one foot on the floor and knees bent. 10 reps per leg, 20 total.

Begin with 90-degree legs overhead. For 5-10 seconds, slowly lower your legs four to five inches to hover in the air. Resume at 90 degrees for 10 reps.  

Upright, arms overhead. Bend your knee and touch your hands. Finish 10 reps on one side, then switch legs. 

Press into a side plank with one elbow under your body. Restart with your core after lowering your hip to hover just below the ground. Perform 10 reps on one side, then switch.

Wide-leg squat with straight, apart feet.  Ten reps per side, 20 total, lowering to one knee and then the other with hands behind head. 

Your knees should be bent and feet forward.  Keep your core engaged and feet elevated. Hold your legs in front of you and twist your upper body.Across again. 10 reps/side. 

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