Test the waters
Definition 1 of 1
Pro Tip 1/3Subtle Caution
Implies careful consideration before full commitment; often used when unsure about outcome. 
She decided to test the waters by submitting her artwork to smaller galleries first.
Pro Tip 2/3Initial Exploration
Suggests gathering information or a reaction without making a significant investment. 
They tested the waters with a soft launch of their product in a select market.
Pro Tip 3/3Casual Inquiry
Used when someone informally checks interest or opinion, often in conversation. 
Just to test the waters, he mentioned his new idea during the team meeting.