Let suppose in your store there is a category called Men and under that a subcategory called Jackets. You want to change the order/layout of the products in the Jackets category on the front end. 

➢ To do so, select the category Men and then click on Manage Product Position tab, a pop-up window Manage Catalogue Positions with the products of the selected category will be available.

On this page, admin can simply click and select the multiple products whose position needs to be changed on the frontend.

Once the products are listed then we will be able to make in order to move the position of the products as desired.

Once the required changes are click on SAVE, then on frontend refresh the page to view the latest changes made. To see changes we need to select Position Wise option in sort by select box (as given in below screenshot).