The people at the American Council on Exercise (ACE) know what they are talking about. ACE was founded in 1985 and offers certifications, training, and education for fitness professionals. They also work within communities to promote fitness and wellness programs across the nation. There is a wealth of information on their website as well as numerous workouts, many of which can be done at home.
One, specifically titled At-home (no equipment) workout, is a full body program using your own body weight for resistance. As with any well-rounded workout, it starts with a warm up before moving into the resistance moves. The great thing about this website is that each move has photographs of the proper form, along with detailed instructions. A list of the muscles used in each exercise is provided to know exactly what you are working. The workout time varies depending upon how familiar you are with the exercises and how long of a break is taken between reps. For best results, plan on spending at least 30-40 minutes.
The ACE website is an excellent source for fitness beginners who are looking for information on how to correctly do exercises and for the more advanced who perhaps want to pursue certification to teach.