I start by reading the text or recommended reading like a novel. I don't worry about retaining info or memorization. Then I go through the power points ext. over and over till it sticks.
When you start med school (at least in the US) you will have to do trial and error till you figure out what works best for you, everyone learns differently. The sheer volume of information is something you can't prepare for until you get in.
2 things will eventually happen as you progress through school.
1. Brain plasticity will kick in and you will be able to assimilate information faster and in greater quantities than you ever thought possible.
2. Over time the material won't all be new to you. Eventually you begin to see the same concepts over and over again. As this happens you won't have to read the full texts as much and can rely more and more on review books (first aid, step up, ect.) At some point you will have covered the material enough that using question banks and reading the explinations will be the best most efficient way to do most of your studing. By the time you are studying for step 2 question banks will probably be how you use 65-75% of your study time.
Of course everyone is different but the above is generally how it goes for alot of people I know.
That's what worked for me, it will be trial and error to find what works for you.