The other method is to deliberately ensure an overlap so that it's easier to find the same landmarks on multiple maps. The zoom-levels introduced in the Pretty Scary Update make the 'overlap' technique of little benefit on any map at zoom level 0 (none) through 3, because an overview map at the next zoom level 'stitches' the maps together.

Regardless of which technique is used, it's helpful to be systematic in the order you craft the maps. For example, you might make Map #0 (prior to the Pretty Scary Update this was designated 'map_0') at the center of the area you want to cover. When maps are crafted (eight paper surrounding a compass) they are initially 'Empty Maps' (data value 395). Holding an empty map and right clicking with it will activate it (data value 358) and draw the current terrain to a radius of 100-120 blocks. The map will be centered on a block that is a multiple of 128 on the x & z axis and will cover an area of 128×128 blocks. Thus, if you are at or near the center block, a zoom-level 0 map is nearly complete when crafted from an empty map.

If you want to keep that map, you should duplicate it at that point by placing it and an 'Empty Map' on your crafting area or table.

City map minecraft 1.8