Somerville by Design is hosting a 3-day design charrette in Union Square that kicks off today to get the community’s ideas for what the neighborhood will look like in the future. Community members are invited to stop in the former Union Square Post Office, 237 Washington St., anytime from 10 a.m. to 8 p.m. on Monday, March 9 and Tuesday, March 10, and from 10 a.m. to 5 p.m. on Wednesday, March 11. There will also be scheduled discussion groups happening throughout the day on Monday and Tuesday, and on Wednesday night from 7:30-9 p.m., the pin-up presentation will showcase ideas generated by the community through the charrette for the future of Union Square. For more information, visit somervillebydesign.com.