Since everyone is different and each drug is different (not even mentioning cross tolerance/partial cross tolerance between different dissociatives), I recommend taking the path of self-discovery to tune into your personal sweet spot. I like to think of use as a ratio of on days to off days. If you want to maximize use and hit the sweet spot but also keep it (relatively) safe I would start around a ratio of 1:4 and go from there. For instance, use 2 days out of a week, and every few weeks take a slightly longer break by using only once that week. Some drugs, like MXE, work pretty well using up to 2 or 3 days in a row (even with multiple redoses each day as long as they arent large doses), while drugs like DXM work better with at least a few days in between doses.
I've used 3-meo-pcp many days in a row, and as long as you don't redose into oblivion and have a ground on reality you can have some serious antidepressant effects and be very functional. But you will definitely want to cycle it by giving a couple days off for each day you used it. so 3 days in a row followed by 6 days off for instance. However, the most sustainable use is only on weekends. I know a guy who has been doing that a long time and is still basking in the magic.