Practice! Or use a Dynamap.
There’s an old Charles Wright joke about a guy who had a map that was an exact 1:1 scale replica of the earth. But he had no place to open it up. Well, the new lenticular Dynamaps for Tourists, published by Urban Mapping, are way cooler than that. On one side of a map is a sophisticated polymer substrate that superimposes three separate color images of Manhattan streets, subways and neighborhoods. Each image is laid down in an alternating strip that’s sliced 1/300th of an inch wide. Tilt the map slightly and, as if by magic, the street grid, subway network, and neighborhoods are revealed one at a time. It’s like a technically advanced version of the prizes you found at the bottom of a Cracker Jack box. But much hipper. Maps are printed on heavy coated stock and fold into quarters for easy handling. Currently available is the map of lower Manhattan from 70th Street to South Ferry. Check it out at www.urbanmapping.com.