Just a word of caution, not all chameleons should receive the same frequency or amounts of supplementation.
Because Fichers (and ssp.) are montane species, their response to supplementation is dangerously sensitive. I personally lack the required in depth knowledge to offer a suggested tried and tested routine, however there is probable raise for concern for dusting montane species, and there is potential for a good gutloading system to provide all the necessary nutrients without dusting.
Hopefully those that have done personal research and are directly working and studying montane species, specifically Fishers and Tavets will drop some more relevant information than I have just offered.