Look for wilting plants and moisture. I think I am the pro on overwatering because I've killed nearly every plant I had in my life this way. Well combo of over and under LOL. Anyway, If it looks like the soil is wet and mushy, it's too wet!! You shouldn't water until the soil is dry to the touch. They say to stick your finger into the soil and if you feel any moisture, it doesn't need water. Take it from a person who didn't water her plant for months and left it out on a balcony, they are more likely to live with a bit of dryness than wetness. It's a weed, it can survive with little care. Too much care kills.