Here's how: Open up a professional game with the SGF viewer of your choice, jump to move 4 and then decide where you would like to move next. Then see what the professional did. If the professional chose a move different than yours, think about why their move was better ( it was). Then do the same with the next move, etc.
Although you might find that the professional tends to be rather tight-lipped, chances are that once you see the their move, the fault of your own reasoning will become self-evident. I've tried this now a few times, and it's astonishing how often, without saying a word, the professional tells me to adhere to the fundamentals and not try something whacky.
I was going to title this "Free Professional Teacher," but I decided I didn't want to tick everybody off.