not to scare you... but depending on the type of succulent you have (some are more rot prone than others) and to a degree your personality.
your far... far... more likely to Overwater than underwater. This is the old phrase kill with kindness. These plants have adapted to go long periods without water. Succulent roots are kind of like the old saying 'horses to water' they drink and drink and don't know when to stop. You have to be the one to know when enough is enough.
Signs of overwatering include death of the plant, brown mushy stems or yellowing leaves.
Watering cacti and succulents is an art better error on the side of caution.
