So there are a few ways of creating custom buttons in SharePoint however, I like my buttons to be noticeable so I tend not to use the standard button however, I’ve shown below how to create buttons using basicbutton, Bootstrap & CSS.
There could be a number of reasons as to why this may be useful, my reason being is the quick launch navigation as it is, is rather packed and therefore trying to use this functionality requires a lot of scrolling down every time. Fortunately you can place some script on the page to push the Metadata navigation to the top of the quick launch, code courtesy of Steve Borgwordt.
Within your list, edit the page and insert a Script editor webpart (Found in Media and Content under the Categories section). Add the following code below.