General synonyms:
* Cheerful
* Happy
* Merry
* Joyful
* Lighthearted
* Good-humored
* Pleasant
* Friendly
* Hearty
Synonyms with a more playful or humorous connotation:
* Jocular
* Waggish
* Facetious
* Merry
* Sprightly
* Spirited
* Zestful
Synonyms with a more robust or hearty connotation:
* Robust
* Hearty
* Stout
* Bubbly
Synonyms emphasizing a positive and energetic attitude:
* Enthusiastic
* Animated
* Spirited
The best synonym for "jolly" will depend on the context of your sentence and the specific meaning you want to convey.