I'd suggest that you sit down and think realistically through a typical day and work out where you can fit the exercise in.
Can you fit in a half hour DVD in the morning before work (if you do work)? For example, I get up at 7.30 and don't need to leave the house until 8.45 - which is, if I make myself actually move rather than sitting on the sofa and feeling like death (I hate mornings!), plenty of time to fit in the half hour Jillian Michaels DVD I'm doing at the moment and have a five-minute shower, as well as breakfast etc. after.
During the day, do you have a chance to go on a fifteen minute walk at a good pace? I have my lunch, and then I leave the office and take a walk to get the blood moving!
Or how about after work? I used to think that going to the gym after work would take up most of the evening - but if my gym bag is packed and ready to go, I can go out and do 30 mins and be back home at the same sort of time I'd usually start dinner. (What would I have done with that time otherwise? Had a cup of tea and watched some telly probably!)
Hope these examples help!
As for body magic awards, for bronze you need to do 45 mins of exercise a week, over at least 3 days (eg 15 mins x 3 days), maintained for a month. Silver is 6 sessions of 15 mins or 3 of 30, spread over 3-5 days, maintained for 4 weeks. Gold is 5 sessions of 30 mins over 5 days, maintained for 8 weeks. I think the main idea behind body magic is to build up slowly and to make being active pretty much every day a habit rather than a chore!