Sisterlocks are quite fragile, and the patented Sisterlock care methodology is best designed to support the tiny size of each loc. Depending on how many Sisterlocks you have, it may be necessary to combine a few of your locs to ensure their strength.
However—don’t do anything until you have gotten the chance to talk with a Sisterlock-certified maintenance technician to examine your options. They have the best understanding of your hair, so they will be able to give you the most sound advice. Microlocs can be maintained “traditionally” with a twisting product or via basic interlocking.
If your maintenance technician recommends twisting for you, I recommend a product without wax; if you are very concerned about your hair health, here is a list of other ingredients that many other natural hair enthusiasts avoid to avoid dryness and/or buildup. However if they suggest interlocking, a tool may be a necessary one-time investment to make maintenance quicker and perhaps less likely to cause damage. Interlocking can certainly be done without a tool, but this is usually done on larger locs than microlocs.
Sorry I can’t be of more help! I hope you found something useful in this message. 🙂