What are 'trust seals' or 'trust badges' and where should I place them to reduce cart abandonment?

I've been running my online fashion boutique for three years now, and cart abandonment has been a constant headache. Recently, I noticed that despite having great products and competitive pricing, potential customers seem hesitant during checkout. They browse, add items to cart, but then... nothing. Just abandoned carts. It's frustrating because I know these are potential sales slipping through my fingers. I started researching why this happens and kept hearing about 'trust seals' and 'trust badges'. Initially, I thought they were just fancy graphics, but then I learned they're actually psychological triggers that can significantly reduce customer anxiety. My biggest concern is making my store look credible and secure, especially since we handle sensitive payment information. I want customers to feel confident that their data is protected and that we're a legitimate business. But I'm also worried about cluttering my clean design or making the site look too busy with random badges. I need a strategic approach that enhances trust without compromising the aesthetic I've carefully built.