In a 2011, researchers studied 5,000 households by tracking purchases and happiness for over four years. They found that in spending money what made people most happy is making purchases designed to create positive experiences. For example, buying materials that allow you to pursue a hobby, travel that creates lasting memories, gifts for friends and family, games that cultivate quality time, or entertainment such as theater or concerts.
This makes the case for either reinvigorating a hobby you already love like gardening, knitting, cooking, making jewelry, pottery, painting, etc., or picking up a new hobby. Creating happiness through intangible experiences like playing a guitar, dancing, or forming a glass bead will naturally build more joy into your life rather than buying a stunning car that takes you back and forth to work.