You really don't ever win at Jenga---you just try to not lose. You pay close attention, watch others, try to keep things in balance. You carefully select the ones that are ready to move, and move them up to the top. There are quite a few that aren't ready to move yet but as things change, so do the pressures and forces exerted on each. As things grow higher, you can't help but reach higher yourself.
Concentrate on individual moves, not an overall strategy. Sometimes the ones at the bottom are the easiest to move to the top.