West wears mostly brown suede chelsea boots with light washed denim. Topping it with either a long tee from his Yeezy's collection or just a plain t-shirt with a coat or bomber jacket over it.
Styles wears the chelsea boots with a more classic Rock n Roll style. Styles often wears black leather and brown suede chelsea boots (Yves Saint Laurent) with dark/black jeans. Topping it off with either a loose folded patterned button down shirt or simply; t-shirt.
Disick follows the same style as Kanye but a little bit more watered down. Disick wears mostly suede chelsea boots with washed grey or light denim jeans. Topping it off with a sweatshirt/long sleeve shirt or simply plain t-shirts with a jacket over it.