There’s no better deal than “Free” (except, I guess, when you don’t want something, but that’s definitely not the case here…) and tomorrow, April 3, from noon to 7:00 p.m., at the Supima Pop-Up Store (72 Greene St., between Spring and Broome) you can stop in to pick up and paint a 100 percent cotton T-shirt of your very own. Plus, they’ll give you cocktails and snacks. All for free!