Hahnemann dilution (H, e.g., CH) - multiple flask method of preparation.

However, for preparing potencies higher than 200C, the Korsakov method is often employed. The Korsakovian method is simpler and quicker. Korsakov's method involves using the same container for each serial dilution, while Hahnemann's method uses a different container for each serial dilution.
Korsakovian dilutions (K, e.g., CK) - single flask method of preparation

The Korsakov method was adopted favourably by physicians and pharmacists. Jahr stated, in 1841, "for dilutions one does not wish to keep, the obtained dilution can be emptied out and the same flask can be filled with one hundred drops and shaken one hundred times in order to achieve the next dilution". Although Hahnemann's method is scientifically accurate, the Korsakovian method lends itself well to computerisation and automation, rendering it the preferred choice for very high potencies in many countries.
It is believed that by using the same container the final remedy contains the energy pattern of all the potencies up to and including the final potency, allowing the patients body to use the most effective potency for the condition.