Sometimes it feels like you're alone against the wall. You've lost all your other pieces. In order to win it seems you've got to singlehandedly outmaneuver the whole other side.
Get the upper hand somehow and take command of the board. Even if you've got no team left, don't let your team down.
Try to keep the biggest stones in check and don't let any other troublesome pieces, that are starting to look like they're going fall on you, get out of position.
Remember it's all a game of strategy. You've got the advantage of intelligence. And besides, stones don't usually move on their own.
Though your playing for 'keeps', still try to have fun, even if the stones beat you some days.