Here you can define what will be the order of your tiles using the internal name of one of your list colunms name.

You will need to type the internal name of the list column on the Order by text box - we will sort the documents according to the value you enter.

Here is what you need to do to check a column's internal name: 1. Access Site contents and open your list; 2. On the top menu, click on List and then List Settings (or Settings > List Settings); 3. On the Columns section, click to open the colum name you want to use; 4. Inside, on the URL look for "...&Field=...".
5. Copy the internal name; 6. Now paste the name on the text box;