Wearing thick clothes in the summer may actually have the opposite effect of what you intend. Thick clothing can hinder the natural evaporation of sweat from your body, which is an important mechanism for cooling down. In hot weather, it's generally recommended to wear lightweight, loose-fitting, and breathable clothing made from fabrics that allow air circulation, such as cotton or linen. These types of fabrics can help promote airflow and enhance the evaporation of sweat, helping to cool your body.
Additionally, wearing light-colored clothing can also help reflect sunlight and reduce the absorption of heat. It's also important to protect yourself from direct sun exposure by wearing a hat, using sunscreen, and seeking shade when needed.
Ultimately, it's essential to find a balance between covering your skin to protect it from the sun and allowing your body to regulate its temperature effectively. Adapt your clothing choices to the specific weather conditions and your own comfort level.