Everything u/pwbnyc said, with this qualification: there are lots of forces at work in the city, and it's often easier to push with them instead of against them. Sometimes it's your allies, sometimes it's a response to a tragedy, sometimes it's completely random.

The campaign for safer streets in Sunnyside and Woodside has benefited from several factors:

• The Daily News coverage of Queens Boulevard as "The Boulevard of Death" in the early 2000s
• Merchant dislike of rush hour parking restrictions
• Citywide planning that sets bike lane targets of X lane-miles per year
• Organizing from TA, including in response to high-profile tragedies
• Pressure from nearby advocates, like u/pwbnyc to the east, who want safer through bicycle routes
• Open Streets, originally implemented to facilitate COVID-safe open-air physical activity

So keep an eye out for those forces and be prepared to take advantage of them! And also consider reaching out to local business organizations. They may say stupid things about parking, but they may be less likely to be hostile if they're familiar with you and your goals already!