To get started, simply warm up for a few minutes by doing some light cardio, such as jumping jacks or jogging in place.  

Then, launch into the following exercises: 

Plank: Start in a push-up position with your forearms on the ground. Hold your body in a straight line from your head to your heels for 30-60 seconds 

Crunches: Lie on your back with your knees bent and your feet flat on the ground. Place your hands behind your head and curl your upper body up towards your knees. Hold for a second, then slowly lower back down. 

 Leg raises: Lie on your back with your legs extended straight up in the air. Slowly lower your legs down until they are about 6 inches off the ground, then slowly raise them back up. Repeat 15-20 times. 

Russian twists: Sit on the ground with your knees bent and your feet flat on the ground. Hold a medicine ball or weight in front of your chest and twist your torso to the right, then to the left. 

Bicycle crunches: Lie on your back with your knees bent and your feet flat on the ground. Place your hands behind your head and curl your upper body up towards your knees.  

Cool down: After you finish your workout, cool down for a few minutes by doing some light stretching. 

This will help to prevent muscle soreness.