It's very easy and can be done on your any computer and even cell phone! All you have to do is do some on-line reading. This consists of watching training videos and reading through the theory part of first aid and CPR. On average, this can take anywhere between 4 - 6 hours, depending on the course chosen.
Now that you are versed in the theory of the first aid and CPR component, all you need to do is to come to the in-class portion and perform the actual skill. There will minimal discussion about the theory because you have already undergone the theory training on-line.
Once you successfully demonstrate the practical component of the course, you will undergo a written knowledge evaluation quiz (20-40 multiple choice questions, depending on the course taken). Once you pass the quiz, the instructor will grant you the same first aid and CPR certificate in half the time it took in a traditional class!