Every vinyl floor eventually repeats its pattern. To minimize having two planks that are identical right next to each other, it is important you become familiar with the pattern you are installing and look for conspicuous patterns that will catch the eye. We recommend having 2-3 boxes open at a time, so you can pick a nice range of planks.
Also, make a point of standing up every few planks and taking a larger view of your floor, especially when installing near "focal points" (areas like entryways where individuals are more likely to inspect the floor). This will help you catch repetition that you may have missed while down on your knees.