DO IT YOURSELF: New York City’s M&J Trimming wants to bring out your inner designer. On Aug. 5, the Garment District fixture will launch Project DIY, a new runway- and street-inspired do-it-yourself subscription box service. Developed for those looking to score trendy accessories without breaking the bank, the company enlisted its staff of in-house jewelry designers to curate original accessories designs and then provide subscribers with everything they need to make them at home. The service offers step-by-step instructions and materials from the company’s vast inventory delivered by mail for $30 per month. The company launched a dedicated microsite with more information and an e-mail sign-up.