As the evening are chilly even in the summer, the easiest way to protect yourself from getting cold is using a jacket.
Blazer jackets are mostly used with dresses and formal wear. The fit cut and flattering look provided by blazers make it the best option. If in a dark color, you can use your blazer jacket with all outfits, especially with jeans.
Longer jacket models can be used with dresses and skinny trousers. If used with wide cut trousers, these models can make you look wider than you actually are.
Leather jackets can be used for a edgy look. These jackets can be used with all outfits to make your look a little rebellious.