During the COVID-19 pandemic I’ve had extra time to sew. After my obsession with sewing different mask patterns, I moved on to something new — sewing boxer brief trunks. I experimented with many different patterns. For me, the Gables Boxer Brief from Made for Mermaids (https://www.madeformermaids.com/product/gable/) is the best pattern in terms of ease of sewing and fit.
I buy 1.5 inch (38mm) plush elastic from Strap Crafts (https://strapcrafts.com/collections/1-1-2inch-38mm-wide).
My favorite fabric to use is Angelskin from Discovery Fabrics (https://discoveryfabrics.com/products/angelskin).
I add a piece of ribbon to the back of the waist as a seam cover. This hides where the elastic is sewn together.