The distinctions were very vague.
Many diagrams of "the planets" included Moon, Mercury, Venus, Sun, Mars, Saturn, Jupiter (yes, the Sun was lumped in with "planets" because they assumed it orbited around the Earth).
Constellations were more often referred to as "stars" rather than planets (although planets were sometimes called stars). Sometimes they differentiated movable stars and fixed stars.
The zodiac constellations were frequently drawn as a ribbon to distinguish them from the other constellations.
Many diagrams of "the planets" included Moon, Mercury, Venus, Sun, Mars, Saturn, Jupiter (yes, the Sun was lumped in with "planets" because they assumed it orbited around the Earth).
Constellations were more often referred to as "stars" rather than planets (although planets were sometimes called stars). Sometimes they differentiated movable stars and fixed stars.
The zodiac constellations were frequently drawn as a ribbon to distinguish them from the other constellations.