^ What Switza said is a great idea. If he starts with low numbers to gauge your strategy, he might assume you're using all of your highest numbers for sure wins, thus throw away his low numbers, and you'd still have low numbers to throw away and high numbers to win.
In that case, I'd say start with 6 (since it's black/white, you'd still know whether he played 7 or 8 if he beats you, and depending on his number - ie: if he plays 4 or 5 - he could assume you played 8 to have a definite early lead). That way you'll get a sense if he's conserving high numbers, and if he wins - you know what number he played.
But again, mostly go in with an idea of a strategy, but constantly be on the look out to adapt/change it.