If only saving a small amount, smear the juice and seeds onto a paper towel and let dry. If saving a large amount, squeeze the juice and seeds into a bowl. You can ferment them for a few days to separate the seeds from the pulp, or mix in a tiny bit of Oxyclean and let sit for 30 minutes. Either way, rinse afterward using a fine-mesh strainer, then spread the seeds on a plate and let dry.
Make sure you label them! If you have more than one variety drying at a time, label them before setting them out to dry. I still keep finding paper plates or little baggies filled with unlabelled seeds, because I assumed I’d remember which was which.
Thank you so much for your reply. My garden is very small due to time and space. But hopefully will grow a little more each year as I get better.