Here's my ref sheet for my new fursona. I am trying to make this one stick more by making it androgynous :D
You can draw it more male or more female if you want. Andro is the preferred. In my case, a girl who looks like a skinny boy :D

Tosa Kens or tosa inus as they are also called, naturally have floppy ears. I made mine have cropped ears. I'm not perfect at drawing doggies so don't go EXACTLY by this image for a reference. Take some liberty and artistic license. The ears can be bigger too.

Here's a link on tosa kens for more info: http://tosa-kenclub.eu/