I was a liquid lens cleaner type person until the lens pens came out. Absolutely the best way to clean a lens. They are not that pricey either. Much better at cleaning than tissue and liquid.
But if you have to use liquid. Do not put a drop on the lens! Start with several tissues out and at the ready. Put just a little on a tissue and clean from the center out in a circular motion-quickly. Before the liquid can completely dry. Take a dry tissue and follow up with same circular motion starting from the center and working outwards. If your getting streaks, you using too much fluid. And again, never put a drop directly on the lens! Always on the tissue. :thumbup:
*Not scientifically tested, but was what worked best for me BEFORE the lens pen.