Bid and Ask charts

On my demo account there are charts for both the Bid and Ask of a currency pair. Should I be looking at the chart that is the opposite of my initial move? That is to say, if I want to end up buying USD/JPY, then should I only be looking at the BUY chart for USD/JPY? (I'm assuming that since I would have to first sell USD/JPY, and then buy it back, that the buy chart is what matters most here. Or is my assumption wrong?)

OR, should I be looking at both the Buy and Sell charts of a currency pair equally, since the spread between Bid and Ask plays an important factor in the outcome of my trade/position? Thanks.

IMO, unless you are trading the news, the spread should be relatively static, so I just know that in the course of a transaction, I will lose 3 or 4 pips. I don't care whether I'm looking at Bid or Ask because it is just three or four pips apart.

andersenws