What is the best way to memorize Chinese characters?
It depends on what you mean by memorizing Chinese characters. 


Reading : No decomposition needed.
Writing :

2.1. Handwriting: No decomposition needed.

2.2. Pinyin input: No decomposition needed.

2.3. Wubihua method: No decomposition needed.

2.4. Wubi method: Need to know radicals.


As you can see, only Wubi method requires decomposition of Chinese characters. Since most of Chinese people are not able to use Wubi and not willing to learn it, because of its complexity, we can conclude that decomposition of Chinese characters is not necessary to memorize them.