Use rmtheme portfolio shortcode, we display portfolio as gird view in masonry style. In this type we can enable category filter at top of grid view. sometimes we need pre-select of filter. in this case, rmtheme added this features in version 5.2.1. Now use just need to add extra parma in url in get style. for example we need to display retail category items by default instead of all items. For retail(slug) category need to browse like
/?pcategory=retail
For preselect or default select using this way.