Try this:
"Start by lying face down on the floor with your hands by your shoulders, the palm of your hands flat on the floor. Your feet should be about a foot (30cm) apart and when you push up to the top of the position you should keep your head in line with your body; it's easier to maintain this position by looking down. As you execute the push-up, pull your tummy button towards your back and squeeze your bottom muscles. Then lower down, about two inches (5cm) off the floor. This is the basic push-up. If, however, you are coming at this with no experience, you should do the push-up resting on your knees instead of your feet. Apply the same technique and keep your head in line with your back. To increase the difficulty of the exercise change the position of your hands. By moving your hands closer together, you'll feel the effort in the back of your arms as well as your chest. Or turn the palms of your hands on the floor so your fingers are facing each other; this will place greater emphasis on your chest muscles. Alternatively, if you really want to increase the intensity ask someone to apply a light pressure on your back. The added resistance will make the move harder and will develop the toning even quicker."
It's from a recent article in The Times by Gabby Logan (10.06.06).
A long time ago, spelling and punctuation were unstandardised. Now we're regarded as uneducated if we can't get it right. It would be nice to think that one day people will be writing to The Times about pieces like this one:
"Sir: I was dismayed to read the article on push-ups in yesterday's Times. As every schoolboy knows, procedural instructions should always be presented in numbered steps, with informative headings and a diagram."