I think the best foreplay would be to be start the evening on a completely non sxual basis, maybe have some food and a few drinks, start flirting a little maybe. Don't touch each other at al. Then slowly start making suggestive comments to each other. Then describe exactly what you want to do to each other, from undressing them to kissing them all over, stroking each others private parts. But not actually touching. Then excuse yourself, go upstairsand come back down wearing soemthing very sexy, lingerie perhaps for the lady. The rest will take caer of itself