SOAK, THEN DRY
Your succulent should be watered whenever the soil is completely dry. When you water, make sure to soak the soil completely.
Once per week is a good start, but adjust as needed depending on when your soil is dry and what your succulent leaves look like.
SIGNS OF PROBLEMS
Yellowing leaves are usually a sign of too much water.
Limp, dull leaves are generally a sign of not enough water.